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Grade 7 - Science and Technology
THIRD QUARTER EXAMINATION
THIRD QUARTER
Force, Motion and Energy
Motion in One Dimension
describes the motion of an object in terms of distance or displacement, speed or velocity andacceleration
1. When is an object considered to be in motion?I. When its position changes with respect to a point of reference.II. When its distance changes with respect to a point of reference.III. When its direction changes with respect to a point of reference.A. I and II only C. II and III only
B. I and III only D. I, II and III
The data below where obtained from a 400-meter dash competition.
Female Athlete Recorded Time Male Athlete Recorded Time
1 27.5 1 23.5
2 27.1 2 22.8
3 26.2 3 24.0
4 27.8 4 23.8
2. Which of the following states is/are NOT true?I. The female athletes are faster than the male athletes.II. Compared to the speed of the fastest female athlete, the average speed of the fastest
male athlete is slightly less.
A. I only C. both I and II
B. II only D. Neither I nor II
3. Which of the following graphs shows that the objects motion is accelerating?
4. An object used as reference point to determine the motion should beA. stationary C. changing direction
B. accelerating D. decelerating
5. When is an object considered to be in motion?I. When its position changes with respect to a point of reference.II. When its distance changes with respect to a point of reference.III. When its direction changes with respect to a point of reference.
A. I and II only C. II and III only
B. I and III only D. I, II and III
A B
C
D
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6. When is an object considered to be in motion?I. When its position changes with respect to a point of reference.II. When its distance changes with respect to a point of reference.III. When its direction changes with respect to a point of reference.
A. I and II only C. II and III onlyB. I and III only D. I, II and III
7. How will you describe distance from displacement?I. A girl walking on the foot-walk from canteen to library, while her friend walk across
the canteen to library.
II. A boy and a girl walk slowly in the foot walk from canteen to library.A. I only C. I and III
B. III only D. none of these
8. When is an object considered to be in motion?I. When its position changes with respect to a point of reference.II. When its distance changes with respect to a point of reference.III. When its direction changes with respect to a point of reference.
A. I and II only C. II and III only
B. I and III only D. I, II and III
9. What is the speed of the tortoise if it took 5 hours to travel a distance off 3 km?A. 1.2km/h C. 2.5km/hB. 0.6km/h D. 0.8km/h
10. Which of the following is true about the object that travels 7 meters to the left, then 3 meters up,then another 7 meters to the right?
A. The displacement if the of the object is equal to 17 meters.
B. The total distance travelled of the object is equal to 17 meters.
C. The displacement of the object is equal to 17meters.
D. The total distance travelled by the object is equal to 17 meters down.
11. Which statement about the movement of an object with zero acceleration is true?A. the object must be at rest
B. the object must be slowing down
C. the object maybe speeding
D. the object may be stopping
12. When is an object considered to be in motion?I. When its position changes with respect to a point of reference.II. When its distance changes with respect to a point of reference.III. When its direction changes with respect to a point of reference.
A. I and II only C. II and III only
B. I and III only D. I, II and III
13. Which of the following is true about the object that travels 10 meters west, then 4 meters North,then another 10 meters to the East?
A. The displacement if the of the object is equal to 24 meters.
B. The total distance travelled of the object is equal to 24 meters.
C. The displacement of the object is equal to 24 meters.
D. The total distance travelled by the object is equal to 24 meters down.
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14. When is an object considered to be in motion?I. When its position changes with respect to a point of reference.II. When its distance changes with respect to a point of reference.III. When its direction changes with respect to a point of reference.
A. I and II only C. II and III onlyB. I and III only D. I, II and III
15. When is an object considered to be in motion?I. When its position changes with respect to a point of reference.II. When its distance changes with respect to a point of reference.III. When its direction changes with respect to a point of reference.
A. I and II only C. II and III only
B. I and III only D. I, II and III
16. It refers to the shortest distance between the objects two positions, like the distance between itspoint of origin and its point of destination, no matter what path it took to get that destination.
A. distance C. motion
B. displacement D. speed
differentiate quantities (in terms of magnitude and direction)using the concepts of distance vsdisplacement and speed vs velocity
17. Which of the following is TRUE about an object that travels 7-meters to the west, then 2-metersnorth, then 7-meters east?
A. The displacement of the object is equal to 16 meters.
B. The displacement of the object is equal to 16 meters down.
C. The total distance travelled by the object is equal to 2 meters.
D. The total distance traveled by the object is equal to 16 meters.
18. Which of the following is true about the object that travels 10 meters to the left, then 5 metersup, then another 8 meters to the right?
A. The displacement if the of the object is equal to 23 meters.
B. The total distance travelled of the object is equal to 23 meters.
C. The displacement of the object is equal to 23 meters.D. The total distance travelled by the object is equal to 23 meters down.
19. Which of the following is true about the object that travels 5 meters to the left, then 2 meters up,then another 5 meters to the right?
A. The displacement if the of the object is equal to 12meters.
B. The total distance travelled of the object is equal to 12 meters.
C. The displacement of the object is equal to 12 meters down.
D. The total distance travelled by the object is equal to 12 meters down.
20. Which of the following fly the fastest?A. A heron that flies 600m in 60 seconds
B. A duck that flies 60m in 5 seconds
C. A seagull that flies 300m in 10 seconds
D. All of them take up the same speed
21. Which of the following is true about the object that travels 5 meters to the left, then 2 meters up,then another 5 meters to the right?
A. The displacement if the of the object is equal to 12meters.
B. The total distance travelled of the object is equal to 12 meters.
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C. The displacement of the object is equal to 12 meters down.
D. The total distance travelled by the object is equal to 12 meters down.
22. Which of the following is true about the object that travels 5 meters to the left, then 2 meters up,then another 5 meters to the right?
A. The displacement if the of the object is equal to 12meters.
B. The total distance travelled of the object is equal to 12 meters.C. The displacement of the object is equal to 12 meters down.
D. The total distance travelled by the object is equal to 12 meters down.
23. What is the average speed of the jeepney that travel 200km in 4hours?A. 50km/hr C. 30km/hr
B. 500m/s D. 25km/hr
The data below where obtained from a 400-meter dash competition.
Female Athlete Recorded Time Male Athlete Recorded Time
1 26.5 1 22.4
2 26.1 2 21.9
3 25.3 3 23.0
4 26.7 4 22.6
24. Which of the following states is/are true?I. The male athletes are faster than the female athletes.II. Compared to the speed of the fastest male athlete, the average speed of the fastest
female athlete is slightly less.
A. I only C. both I and II
B. II only D. Neither I nor II
25. Which of the following differentiate speed from velocity?A. Speed describes how fast an object moves while velocity tells about speed and
direction of travel
B. Velocity describes the change in speed while speed describes the direction travelC. Speed describes the velocity of a moving objectD. Speed describes the time of travel while velocity describes the total displacement
26. In describing the motion of an object. We do not describe the speed but consider also its velocity.Which of the following describes velocity?
A. 15 meter C. 20 meters up
B. 15 N, 120E D. 20 meters down
27. Which of the following is not acceleration?A. rate of change in velocity
B. rate of change n displacement
C. rate of change of speed in a particular direction
D. rate of change of motion in a particular direction
28. Which statement differentiates displacement, distance, speed and velocity?I. Displacement always follow a straight line, distance do not.II. Speed has no direction, velocity have.III. Distance is equal to displacement plus direction.IV. Distance and displacement both have speed and velocity.
A. I and II only C. III and IV only
B. II and III only D. all of the above
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29. Which does not belong to the group?A. 300 km/hr C. 20 m/s
B. 20 km/s D. 40 m/s East
30. Which of the following is an example of velocity?A. 259 meter C. 200 km/hrB. 100 meter/second D. 320 km/hr going South of Capiz
31. Which of the following is an example of displacement?A. 180 km/h North C. 20 km/h/min, 45 North of East
B. 60 km/h D. 100 km, 36 West of South
32. Which of the following is true about the object that travels 5 meters to the left, then 2 meters up,then another 5 meters to the right?
A. The total distance travelled of the object is equal to 12 meters.
B. The displacement if the of the object is equal to 12meters.
C. The total distance travelled by the object is equal to 12 meters down.
D. The displacement of the object is equal to 12 meters down.
creates and interprets visual representation of the motion of objects such as tape charts andmotion graphs
33. Referring to the diagram above, what is the final position of the ball after 15 seconds?A. 10m B. 5m C. 15m D. 0m
34. Which of the following graphs shows that the objects acceleration increase?
35. The graph shows the process made by turtle moving along a straight line.
If the turtle keeps moving at the same speed, how long will it take to travel 12 cm?
A. 12 seconds C. 25 seconds
B. 20 seconds D. 30 seconds
A B
C
D
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36. Which of the following graphs shows that the objects acceleration increase?
37. Which of the following graphs shows that the objects acceleration increase?
38. Which of the following situation represent the motion of an object?A. ball on the table C. picture frame on the wall
B. a car moving forward D. the glowing candle
39. Which of the following graphs shows that the objects motion is accelerating?
40. Martin rides a bicycle at 7m/s. Ten seconds later, he is driving at 10m/s. What is Martinsacceleration?
A. 0.3m/s C. 0.4m/s
B. 0.6m/s D. 0.5m/s
41. Which of the following graphs shows that the objects acceleration increase?
A B
C
D
A B
C
D
A B
C
D
A B
C
D
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42. Which of the following graphs shows that the objects acceleration increase?
43. Which of the following graphs shows that the objects acceleration increase?
44. Which of the following graphs shows that the objects acceleration increase?
45. Which of the following graphs shows that the objects acceleration increase?
The data below where obtained from a 400-meter dash competition.
Female Athlete Recorded Time Male Athlete Recorded Time
1 26.5 1 22.4
2 26.1 2 21.9
3 25.3 3 23.0
4 26.7 4 22.6
A B
C
D
A B
C
D
A B
C
D
A B
C
D
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46. Which of the following states is/are true?I. The male athletes are faster than the female athletes.II. Compared to the speed of the fastest male athlete, the average speed of the
fastest female athlete is slightly less.
A. I only C. both I and II
B. II only D. Neither I nor II
47. Based on the diagram below, is it possible to get zero displacement?
A. no, because theres equal distance and displacement travelled by the objectB. yes, when the object goes back to their starting positionC. no, because distance differs to displacementD. yes, distance is equal to displacement
Waves
infers that energy, like light and sound, travels in the form of wave48. Energy from the sun reaches the earth though
A. Ultraviolet waves
B. Infrared waves
C. Mechanical wavesD. Electromagnetic waves
49. Light is an electromagnetic wave. Which characteristic is common in all electromagnetic waves?A. speed C. amplitude
B. frequency D. wavelength
50. Energy from the sun reaches the earth thoughA. Ultraviolet waves
B. Infrared wavesC. Mechanical waves
D. Electromagnetic waves
51. What is the movement of water molecules when a wave passes by?A. it moves in a circular motion
B. it moves in all direction
C. it moves in straight line
D. it moves up and down
52. Energy from the sun reaches the earth thoughA. Ultraviolet waves
B. Infrared waves
C. Mechanical waves
D. Electromagnetic waves
53. Energy from the sun reaches the earth thoughA. Ultraviolet waves
B. Infrared waves
C. Mechanical waves
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D. Electromagnetic waves
54. Sound energy can travel through transverse wave while light energy can travel in space throughA. mechanical waves
B. electromagnetic waves
C. surface waves
D. both A and C
55. Mechanical Waves transport energy from one place to another throughA. alternately vibrating particles of the medium.
B. particles traveling with the waves.
C. vibrating particles and traveling particles.
D. None of the above.
56. A pulse sent down a long string eventually dies away and disappears. What happens to its energy?A. the energy disappears with the wave
B. the energy remains along the length of the string
C. the energy is transferred from the wave to the environment
D. the pulse does not carry the energy
57. Mechanical Waves transport energy from one place to another throughA. alternately vibrating particles of the medium.
B. particles traveling with the waves.
C. vibrating particles and traveling particles.
D. None of the above.
58. Energy from the sun reaches the earth thoughA. Ultraviolet waves
B. Infrared waves
C. Mechanical waves
D. Electromagnetic waves
59. What happens when waves pass by?A. energy travels in the form of waves
B. particles vibrate alternately to transport the energy of the wave
C. waves can set other objects to moveD. energy travels in the direction of the waves
60. Heat of the sun is one of the reasons why life on Earth exists. The heat of the from the sunreaches the earth though
A. Ultraviolet waves
B. Infrared waves
C. Mechanical waves
D. Electromagnetic waves
61. Energy from the sun reaches the earth thoughA. Ultraviolet waves
B. Infrared waves
C. Mechanical waves
D. Electromagnetic waves
62. Energy from the sun reaches the earth thoughA. Ultraviolet waves
B. Infrared waves
C. Mechanical waves
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D. Electromagnetic waves
explains how waves carry energy from one place to another63. Mechanical Waves transport energy from one place to another through
A. alternately vibrating particles of the medium.
B. particles traveling with the waves.C. vibrating particles and traveling particles.
D. None of the above.
64. Mechanical waves transport energy from one place to another through ____________.A. Particles traveling with the wave
B. Vibrating particles and traveling particles
C. Alternately vibrating particles of the medium
D. None of the above
65. Mechanical Waves transport energy from one place to another throughA. alternately vibrating particles of the medium.
B. particles traveling with the waves.
C. vibrating particles and traveling particles.
D. None of the above.
66. The highest point and lowest point of a wave areA. amplitude C. wavelength
B. crest and trough D. frequency
67. Mechanical Waves transport energy from one place to another throughA. alternately vibrating particles of the medium.
B. particles traveling with the waves.
C. vibrating particles and traveling particles.
D. None of the above.
68. Mechanical Waves transport energy from one place to another throughA. alternately vibrating particles of the medium.
B. particles traveling with the waves.
C. vibrating particles and traveling particles.D. None of the above.
69. Which of the following statement is NOT TRUE about wave?A. Wave is a periodic disturbance that moves away from a source and carries
energy with it.
B. Waving of hands is a common gesture that people do to catch someone
attention or to convey farewell.
C. Periodic wave can be regarded as a series of pulse.
D. Wave can move without force and energy.
70. Mechanical Waves transport energy from one place to another throughA. alternately vibrating particles of the medium.
B. particles traveling with the waves.
C. vibrating particles and traveling particles.
D. None of the above.
71. In a transverse wave, the individual particles of the medium ____________.A. move in circles
B. move in ellipses
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80. In a transverse wave, the individual particles of the medium ____________.A. move in circles
B. move in ellipses
C. move parallel to the direction of travel
D. move perpendicular to the direction of the travel
81. Energy from the sun reaches the earth throughA. mechanical waves
B. transverse waves
C. longitudinal waves
D. electromagnetic waves
82. _________ waves occur when the individual particles of a medium move perpendicular to thedirection of travel, while_____________ waves occur when the individual particles of a medium
vibrate back and forth in the direction and ______________ waves do not require a medium to
propagate.
1. transverse waves2. longitudinal waves3. electromagnetic waves
A. II, III and I C. I, II and III
B. III, II and I D. III, I and II
83. In a transverse wave, the individual particles of the medium ____________.A. move in circles
B. move in ellipses
C. move parallel to the direction of travel
D. move perpendicular to the direction of the travel
84. In transverse wave, the individual particles of the medium wave perpendicular to wave directionwhile longitudinal waves the individual particles of the medium vibrate back and forth to wave
direction but electromagnetic waves
A. can travel with material medium for their passage.
B. can travel without material medium for their passage.
C. can travel in a circular pattern to the direction of wave.
D. can travel in space both circulating and alternating wave pattern.
85. In a transverse wave, the individual particles of the move .A. in circles.
B. in ellipse.
C. parallel to the direction of travel.
D. perpendicular to the direction of travel.
86. Energy from the sun reaches the earth throughA. mechanical waves
B. transverse waves
C. longitudinal waves
D. electromagnetic waves
87. Using a spring, a portion of the wave is alternately compressed and extended. What kind of wave isproduced?
A. transverse waves
B. longitudinal waves
C. chemical waves
D. electromagnetic waves
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88. Which statement distinguishes transverse, longitudinal and electromagnetic waves?A. transverse and longitudinal waves are mechanical waves
B. transverse and longitudinal waves need medium of waves propagation while
electromagnetic wave does not
C. both mechanical and electromagnetic wave have energy
D. both travel in the same direction
89. In a transverse wave, the individual particles of the medium ____________.A. move in circles
B. move in ellipses
C. move parallel to the direction of travel
D. move perpendicular to the direction of the travel
90. Waves occur when the individual particles of a medium move perpendicular to the direction oftravel.
A. mechanical waves
B. longitudinal waves
C. electromagnetic waves
D. transverse waves
91. Which of the following shows the interval that represents a half wavelength?
A. A to E B. B to F C. A to B D. C to E
92. Mechanical waves transport energy from one place to another through alternately vibratingparticles of medium while electromagnetic wave
A. needs medium too
B. travels in vibrating particles
C. travels without medium
D. none of the choices
use a model to demonstrate a relationship among frequency, amplitude, wavelength, and wavevelocity
93. The amplitude of the wave in the diagram above is given by letter _____.A. B B. C C. A D. E
94. The wavelength of the wave in the diagram below is given by a letter
A. A to E B. B to F C. A to B D. C to E
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Consider the diagram below to answer the question.
95. The wavelength of the wave in the diagram above is given by letter ___. Ans. A96. Supposed you observed an anchored boat to rise and full once every 4.0 seconds as waves whose
crest are 25 meters apart pass by it. What is the frequency of the observed waves?
A. the frequency of the waves is 0.25Hz
B. the frequency of the waves is 0.35Hz
C. the frequency of the waves is 0.45Hz
D. the frequency of the waves is 0.55Hz
97. What is the relationship between wave speed, wavelength and frequency?A. wave speed is equal to frequency time wavelengths
B. wave speed is equal to frequency divided by wavelength
C. wave speed is equal to frequency plus wavelength
D. wave speed is equal to frequency less wavelength
98. The higher the frequency of a wave,A. the lower its circles C. the greater its amplitude
B. the shorter its wavelength D. the longer its period
99. The higher the frequency of the waveA. the lower its speed
B. the shorter its wavelength
C. the greater its amplitude
D. the longer its period
100.The higher the frequency of a wave,A. the lower its circles C. the greater its amplitudeB. the shorter its wavelength D. the longer its period
101. Energy from the sun reaches the earth throughA. ultraviolet waves
B. infrared waves
C. mechanical waves
D. electromagnetic waves
102. The vibration of frequency 5Hz sends a wave of wavelength 0.8m down a rope. What is the speedof the wave?
A. 4m/s C. 5m/s
B. 6.45m/s D. 2m/s
103. Which of the following shows the interval that represents a half wavelength?
A. A to E B. B to F C. A to B D. C to E
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104. (Refer to the diagram below) A string of guitar is being plucked in 1 second. Set A is pluck slowlywhile set B is plucked forcedly. What is true on the situation?
A. the higher the frequency the shorter the wavelength
B. the lower the frequency the longer the wavelength
C. the higher the frequency the longer the wavelength
D. there is no correlation in both situations
105.Which of the following demonstrate on inverse relationship among frequency, amplitude,wavelength and wave velocity?
106.The higher the frequency of a wave,A. the lower its circles C. the greater its amplitude
B. the shorter its wavelength D. the longer its period
107. Compare the frequency and energy carried by UV waves to that of visible light, the UV waveshave
A. high energy
B. low energy
C. no energy
D. did not carry energy
108.The higher the frequency of a wave,A. the lower its circles C. the greater its amplitude
B. the shorter its wavelength D. the longer its period
109. Of the following properties of wave, the one that is independent of the others is its A. amplitude C. wavelength
B. wave speed D. frequency
Sound
uses the concepts of wavelength, velocity and amplitude to describe characteristics of soundsuch as pitch, loudness and quality
110. Which of the following best describes a high frequency sound? It has A. low pitch C. low energy
B. high pitch D. A and C
111. Which of the following best describes a low frequency sound? It has A. low pitch C. high pitch
B. low energy D. A and C
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112. Which of the following best describes a high frequency sound? It has A. low pitch C. low energy
B. high pitch D. A and C
113. Sound waves are example of A. transverse wave C. longitudinal waveB. standing wave D. elastic wave
114. Which of the following best describes a high frequency sound? It has A. low pitch C. low energy
B. high pitch D. A and C
115. Which of the following best describes a high frequency sound? It has A. low pitch C. low energy
B. high pitch D. A and C
116. When can we say that a sound has a high pitch, if it hasA. high energy C. high frequency
B. low frequency D. high wavelength
117. Which of the following best describes a high frequency sound? It has A. low pitch C. low energy
B. high pitch D. A and C
118. Which of the following best describes a high frequency sound? It has A. low pitch C. low energy
B. high pitch D. A and C
119. Which of the following best describes a high frequency sound? It has A. low pitch C. low energy
B. high pitch D. A and C
120. What happens to the pitch of the sound when the frequency is high?A. the pitch is also high C. the pitch is alternately high and low
B. the pitch is low D. the pitch is not affected
121. Which of the following best describes a high frequency sound? It has A. low pitch C. low energy
B. high pitch D. A and C
122. The higher the frequency of a sound wave the A. higher the pitch C. shorter the wavelength
B. greater the speed D. greater amplitude
123. Which of the following best describes a high frequency sound? It has A. low pitch C. low energy
B. high pitch D. A and C
124. Which of the following best describes a high frequency sound?A. low pitch C. low energy
B. high pitch D. A and C
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125. High amplitude sounds usually carry large energy and have higher intensity while low amplitudesound
A. carry lesser amount of energy C. carry greater amount of energy
B. higher intensity D. no pitch
demonstrates changes in pitch and loudness using real and improvised musical instrumentstrough fair testing
126. Compared to a thin string of the same length and tightness a thick string produces sound of_______.
A. the same pitch C. higher pitch
B. lower pitch D. lower then higher pitch
127. Compared to a thick string of the same length and tightness a thin string produces sound of_______.
A. lower pitch C. the same pitch
B. higher pitch D. lower then higher pitch
128. In the Sounding Box, compared to a thin rubber band of the same length and tightness a thickstring produces sound of ____________?
A. the same pitch C. higher pitch
B. lower pitch D. lower then higher pitch
129. Sound is heard much louder when it travels inA. Air C. liquid
B. gas D. solid
130. Compared to a thin string of the same length and tightness a thick string produces sound of_______.
A. the same pitch C. higher pitch
B. lower pitch D. lower then higher pitch
131. Compared to a thin string of the same length and tightness a thick string produces sound of_______.
A. the same pitch C. higher pitch
B. lower pitch D. lower then higher pitch
132. Which of the following strings of an improvised musical instrument produces low sound?A. long and thin string C. short and thin string
B. long and thick string D. short and thick string
133. Compared to a thin string of the same length and tightness a thick string produces sound of_______.
A. the same pitch C. higher pitch
B. lower pitch D. lower then higher pitch
134. Compared to a thin string of the same length and tightness a thick string produces sound of_______.
A. the same pitch C. higher pitch
B. lower pitch D. lower then higher pitch
135. Compared to a thin string and a thin rubber band it produces sound ofA. higher pitch C. lower and higher pitch
B. lower pitch D. B and C
136. A man plucked the thin string. What do you think is the sound produce?A. soft C. loud
B. melodic D. low
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137. Which of the following objects will produce sound?A. soft drink C. vibrating objects
B. radio station D. objects under pressure
138. Compared to a thin string of the same length and tightness a thick string produces sound of_______.
A. the same pitch C. higher pitch
B. lower pitch D. lower then higher pitch
139. In a string instrument like guitar, the thick strings will produce A. low pitch C. low energy
B. high pitch D. low and high pitch
140. Compared to a thin string of the same length and tightness a thick string produces sound of_______.
A. the same pitch C. higher pitch
B. lower pitch D. lower then higher pitch
141. The pitch of a high frequency is A. low C. moderate
B. high D. no pitch
explains sound production in human voice box and how pitch, loudness and quality of soundvary from one person to another
142. Which of the following can transmit sound faster?A. wood B. air C. steel D. water
143. Pitch refers to the highness or lowness of sound. Which of the following reasons explain why pitchvaries from one person to another?
A. human beings voice box differ in thickness
B. pitch differs because some people can stretch their voice box while some
cannot
C. both A and B are correct
D. none of the above
144. The loudness of sound wave detected by human ear is mostly determined by the wavesA. amplitude B. intensity C. speed D. frequency
145. People change the pitch of their voice by adjusting the opening of their vocal chords; when theopening is small; the pitch is __________, when the opening is wide, the pitch is ______________.
A. high; low C. low; low
B. low; high D. high; high
146. When we talk or make any sound, our vocal cords vibrate and sound is produced. This sound waveis a ____________.
A. longitudinal wave C. surface waves
B. transverse wave D. shock wave
147. Which of the following medium does the sound can travel fastest and slowest?A. sound can travel fastest in solid and slowest in gas.
B. sound can travel fastest in liquid and slowest in solid.
C. sound can travel fastest in gas and slowest in liquid.
D. sound can travel fastest in solid and gas then slowest in liquid.
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148. Which of the following is not capable of transmitting sound?A. air B. water C. steel D. vacuum
149. How does sound production varies from one person to another?A. shape and size of the mouth C. vibration of vocal chords
B. shape and size of the voice box D. all of the above
150. Which of the following is not capable of transmitting sound?A. air B. water C. steel D. vacuum
151. It is a psychological sensation that differs for different people.A. pitch C. intensity
B. loudness D. quality
152. John shouted very loud. Which part of his body do you think the sound came from?A. in the stomach C. in the mouth
B. in the vocal chords D. in the esophagus
153. Which of the following is not capable of transmitting sound?A. air B. water C. steel D. vacuum
154. ______________ is produced when there is a vibration of vocal chords.A. waves B. sound C. light D. all of the above
155. Which of the following would most likely transmit sound best?A. steel in cabinet C. air in your classroom
B. water in the ocean D. water in a swimming pool
156. In human ear, the __ collects sound waves and focuses them into ear canal. This canal transmitsthe sound waves to the eardrum.
A. hammer C. pinna
B. tympanum D. stirrup
describes how organisms produce, transmit and receive sound of various frequencies(infrasonic, audible and ultrasonic sound)
157. Which of the following would most likely transmit sound best?A. steel in cabinet C. air in your classroom
B. water in the ocean D. water in a swimming pool
158. Of the following source of sound, which is considered as infrasonic?A. breathing C. old subway train
B. amplified rock music D. jet engine
159. Vibrational frequency beyond 20000Hz is called ultrasonic frequencies while extremely lowfrequencies are known as infrasonic frequencies. Which of the following animals can detect
sounds as high as 100000Hz
A. human beings C. dogs
B. cats D. bats
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160. Which of the following is a stringed musical instrument?A. trumpet C. drum
B. violin D. saxophone
161. Which of the following CANNOT detect ultrasonic or infrasonic waves?A. dog C. catB. bat D. human
162. Vibrational frequency beyond 20000Hz is called _________________ while extremely lowfrequencies are known as __________________.
A. ultrasonic; infrasonic C. internal; external
B. infrasonic; ultrasonic D. low; high
163. Which of the following is not capable of transmitting sound?A. air C. steel
B. water D. vacuum
164. Which of the following range of frequency do the dogs and bats detect sound? When human earcan detect sound at a frequency of 2020,000Hz.
A. dogs 50,000Hz above, bats 100,000Hz above
B. dogs 30,000Hz above, bats 90,000Hz above
C. dogs 100,000Hz above, bats 50,000Hz above
D. dogs 25,000Hz above, bats 30,000Hz above
165. Which of the following would most likely transmit sound best?A. steel in cabinet C. air in your classroom
B. water in the ocean D. water in a swimming pool
166. Bats produce ultrasonic sound or ultrasound to locate its prey during nighttime. How do theseorganisms generate the sound?
A. bats generate less than 20 kHz C. bats generate 20 kHz
B. bats generate more than 20 kHz D. none of the above
167. Which of the following would most likely transmit sound best?A. steel in cabinet C. air in your classroom
B. water in the ocean D. water in a swimming pool
168. Which of the following best describes a high frequency sound? It has A. low pitch C. low energy
B. high pitch D. A and C
169. How do birds communicate with each other?A. by their sound C. when they fly
B. by its color of the feather D. by talking
170. Organisms like us are capable of sensing through our ears and can sense within the frequencyrange of
A. 2020,000Hz C. 50,000Hz
B. 20,000 beyond D. 100,000Hz
171. Our ear is a sensitive part of our body that belongs to peripheral auditory system. It can sensefrequency of _______.
A. 2020,000Hz C. 2525,000Hz
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193. Observe the shadow cast by the object shown below. The illustration suggest that
A. light is reflected C. light is a form of radiationB. light is absorbed D. light travels in a straight line
194. According to fair testing that the relation of light intensity and distance from light source isA. the farther the distance from the light source is the lesser its light intensity
B. the nearer the distance from the light source is the lesser its light intensity
C. the farther the distance from the light source the dimmer its light intensity
D. the nearer the distance from the light source is the lower its light intensity
195. Among all the electromagnetic waves (EM), which has the highest frequency?A. infrared radiation C. ultraviolet
B. radio wave D. gamma rays
196. Observe the shadow cast by the object shown below. The illustration suggests that
A. light is reflected
B. light travels in a straight line
C. light is absorbed
D. light is a form of radiation
197. Light is an electromagnetic wave. Which characteristic is common in all electromagnetic waves?A. amplitude C. speed
B. frequency D. wavelength
198. Light is an electromagnetic wave. Which characteristic is common in all electromagnetic waves?A. amplitude C. speedB. frequency D. wavelength
199. Which is the correct way how light travels?200. What evidence is illustrated based on the diagram below
A. light is absorbedB. light is reflected
C. light is a form of radiation
D. light travels in a straight line
201. It is a special kind of refraction that provides us color of light. This phenomenon is observed whenwhite light passes through a prism and travels.
A. dispersion
B. visible spectrum
C. deflection
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D. magnetism
202. How does the wavelength of infrared (IR) compare with the wavelength of ultraviolet (UV) waves?A. infrared waves have longer wavelength
B. infrared waves have shorter wavelength
C. IR waves have the same wavelength as the UV waves
D. IR is not comparable in wavelength with UV waves
203. A phenomenon in which a prism separates white light into its components colorsA. dispersion
B. distortion
C. delusion
D. radiation
204. investigate the relationship between light intensity and the distance from light source through fairtesting
205. How does the wavelength of Gamma-Ray compare with the wavelength of X-ray waves?A. Gamma ray waves have longer wavelength
B. Gamma ray waves have shorter wavelength
C. Gamma ray waves have the same wavelength as the X-ray waves
D. Gamma ray is not comparable in wavelength with the X-ray waves
206. How would you relate the brightness or intensity of light with the distance from the source?A. the nearer the light source, the dimmer is the light and the lower intensity
B. the farther the light source, the dimmer is the light and the lower intensity
C. the nearer the light source, the brighter is the light and the lower intensityD. the farther the light source, the brighter is the light and the higher the
intensity
207. How would you relate the brightness or intensity of light with the distance from the source?A. the farther the source, the brighter is the light and the lower the intensity
B. the farther the light source, the dimmer is the light and the lower the
intensity
C. the nearer the light, the dimmer is the light and the lower the intensity
D. both B and C
208. Based on the experiment result in the diagram below, the light travel in straight line if the surfaceis
A. rough C. wrinkled
B. smooth D. both A and B
209. ROYGVIB is the basic component of white light. Which color of light carries less energy?A. Blue B. Green C. Orange D. Red
210. How do we relate the brightness or intensity of light with the distance from the source?A. the farther the distance, the light becomes dimmer
B. the nearer the distance, the light becomes dimmer
C. the nearer the distance, the light becomes blurry
D. no effect in the brightness regardless of the distance from the source
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221. How does heat transfer?I. It transfers from an object of lower temperature to an object of higher
temperature.
II. It transfers from an object of higher temperature to an object of lowertemperature.
III. It transfers from an object with equal temperature.A. I and II only C. I, II and III onlyB. II and III only D. II only
222. What is the condition necessary for heat transfer to take place between objects?A. the objects must have the same temperature
B. the objects must be of different temperature
C. the objects must have constant temperature
D. both A and B
223. A red-hot iron nail is placed into a kettle or boiling water. Which statement correctly explains theresulting heat transfers?
A. Heat flows from the water to the iron nail because boiling water has more
thermal energy
B. Heat flows from the water to the iron nail since the water molecules have a
higher average kinetic energy
C. heat flows from the iron nail to the water since the iron nail is at higher
temperature
D. heat flows out of the kettle to the cooler surrounding air
224. Light is an electromagnetic wave that travels in space without material medium. Whichcharacteristic of light is different from other electromagnetic wave form?
A. frequency C. color
B. intensity D. wavelength
225. How does heat travel through a pan?A. by radiation C. by dispersion
B. by convection D. by conduction
226. Heat transfer by convection may occur in which of the following?A. metals only C. nonmetallic solidsB. fluids only D. in a vacuum
227. How does heat travel through a pan?A. by radiation C. by dispersion
B. by convection D. by conduction
228. Your mother serves you with a hot soup at breakfast. How does heat travel through the soup?A. by radiation C. by dispersion
B. by convection D. by conduction
229. Which of the following situation best describes that conduction takes place?A. conduction takes place between objects that are in contact with each other
B. the energy from the object of higher temperature is transferred to the other
object through their particles
C. A and B
D. none of these
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230. Heat is transferred to or from solids byA. convection C. conduction
B. radiation D. all of the above
231. It is related to the change on temperature or change in the relative hotness or coldness of anobject.
A. refraction C. conductivityB. heat transfer D. capillary
232. Betchay is making a noodle soup using a pan made of metal. How does heat travel through a pan?A. by radiation C. by dispersion
B. by convection D. by conduction
233. Method of heat transfer where heat energy travels when two objects are in direct contact and arenot equal temperatures.
A. radiation C. convection
B. conduction D. mechanical
explains different modes of heat transfer in terms of movement of particles234. Which of the following situations happen because of convection?
A. Heat from the sand felt by the person walking on the beach.
B. Heat from the sun felt by a person lying on the beach.
C. Sea breeze felt by a person sitting by the beach.
D. Clouds forming over the beach.
235. In what direction does heat transfer/travel though arroz caldo?A. from bottom to top C. both A and B
B. from top to bottom D. neither A nor B
236. Andrea is preparing a noodle soup using a pan made of metal. How does heat travel through thesoup?
A. by radiation C. by dispersion
B. by convection D. by conduction
237. When the object becomes warmer it means that he object _____________.A. it gained energy C. it transfer energy to another object
B. it losses energy D. none of the above
238. One of the methods by which heat is transferred from the object of higher temperature to otherobject through their particles that are close or in contact with each other.
A. convection C. conduction
B. radiation D. none of the above
239. Heat is best transferred to or from solids by A. convection C. conduction
B. radiation D. all of the above
240. How does heat travel through a pan?A. by radiation C. by dispersion
B. by convection D. by conduction
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241. How does heat travel through the soup?A. by radiation C. by dispersion
B. by convection D. by conduction
242. Which of the following is a poor conductor?A. air B. copper C. gold D. ice
243. How does heat travel through the soup?A. by radiation C. by dispersion
B. by convection D. by conduction
244. What happens when air is heated?A. it rises C. it spread in all direction
B. it stays in place D. it move toward the lower elevation
245. Which of the following situations happen because of convection?A. heat from the sand felt by the person walking on the beach
B. heat from the sun felt by a person lying on the beach
C. sea breeze felt by a person sitting by the beach
D. clouds forming over the beach
246. A mother is cooking in a pan. Which of the following methods of heat transfer is NOT taking placein a given situation?
A. convection C. conduction
B. radiation D. none of them
247. Heat transfer takes place when there is a vibrating and colliding particle of objects that are incontact.
A. conduction C. convection
B. radiation D. all of the above
248. How does heat travel through the soup?A. by radiation C. by dispersion
B. by convection D. by conduction
249. The heat in fluids is transferred to cooler regions by currents. These currents are caused bywarmer and less dense pockets of fluids rising in cooler and move dense surroundings.
A. radiation C. convection
B. conduction D. mechanical
identifies poor and good conductor of heat transfer in terms of movement of particles250. Why are cooking utensils provided with wooden handles?
A. Wood is cheaper than steel.
B. Wood is light and easy to handle.
C. Wood is a poor conductor of heat.
D. Wood is more attractive than steel
251. Which of the following explains why the lady/mother is able to hold the handle of the kettle withher bare hands?
1. The handle has high thermal energy.2. The handle has low thermal conductivity.3. The handle is made of good insulator of heat.
A. I and II only C. II and III only
B. I and III only D. I, II and III
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252. Which of the following explains why Andrea is able to hold the handle of the pan with her barehands?
1. The handle is made of good insulator of heat.2. The handle has low thermal conductivity.3. The handle has high thermal energy.
A. I and II only C. II and III only
B. I and III only D. I, II and III
253. Objects that conduct heat poorly are particularly called ___________.A. conductor C. convection
B. insulators D. dispersion
254. ____________ is a good conductor of heat; while ____________ is the poorest conductor of heat.A. silver; paper C. aluminum foil; copper
B. paper; cloth D. glass; wood
255. To most Filipinos, lechon is a part of their occasion. How does heat travel in roasting lechon?A. by conduction C. by radiation
B. by convection D. by compaction
256. In what direction does heat travel through the soup?A. by radiation C. by dispersion
B. by convection D. by conduction
257. In what direction does heat transfer though the soup?A. from top to bottom C. both A and B
B. from bottom to top D. neither A nor B
258. Foam cups are used to keep lemonade cold for hours because Styrofoam is a goodA. color C. insulator
B. conductor D. string material
259. In what direction does heat transfer though the soup?A. from top to bottom C. both A and B
B. from bottom to top D. neither A nor B
260. Which of the following explains why the lady is able to hold the handle of the pan with her barehands?
1. The handle is made of good insulator of heat.2. The handle has low thermal conductivity.3. The handle has high thermal energy.
A. I and II only C. II and III only
B. I and III only D. I, II and III
261. Solids that conduct heat better are good conductors of heat. Which of the following materials arenot good conductors of heat?
A. silver spoon, gold ring
B. aluminum pots, copper wire
C. ice, rubber tire
D. none of these
262. Which of the following is good conductor of heat?A. glass C. porcelain
B. metals D. head rubber
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263. Which of the following explains why the lady is able to hold the handle of the pan with her barehands?
1. The handle is made of good insulator of heat.2. The handle has low thermal conductivity.3. The handle has high thermal expansion.
A. I and II only C. II and III only
B. I and III only D. I, II and III
264. In what direction does heat transfer though the soup?A. from top to bottom C. both A and B
B. from bottom to top D. neither A nor B
265. Materials whose electric charges are free to move within are called conductors. The followingmaterials are examples of conductors EXCEPT.
A. silver C. conductor
B. iron D. rubber
identifies good and poor conductor of heat and describe their specific uses266. In a desert, it is hot in the daytime and cold at night. The walls of houses there are often made of
mud. It is important that the walls are thick. What is the direction of the flow of heat through the
wall in the daytime?
A. Heat transfer is not evident in a desert.
B. In the daytime, heat flows from the outside to the inside.
C. In the daytime, heat flows from the inside to the outside.
D. Heat transfers from object with low temperature to the one with higher
temperature.
267. Of the following materials, which is a good conductor of heat?A. wood B. water C. steel D. soil
268. Which of the following is a good conductor of heat?A. pan C. pot holder
B. polypropylene plastic D. water
269. Which of the objects are considered good conductors of heat?A. metals C. glassB. stone D. paper
270. Which of the following explains why Andrea is able to hold the handle of the pan with her barehands?
1. The handle is made of good insulator of heat.2. The handle has low thermal conductivity.3. The handle has high thermal energy.
A. I and II only C. II and III only
B. I and III only D. I, II and III
271. Which of the following explains why mother is able to hold the handle of the pan with her barehands?
1. The handle is made of good insulator of heat.2. The handle has low thermal conductivity.3. The handle has high thermal energy.
A. I and II only C. II and III only
B. I and III only D. I, II and III
272. Which of the following explains why the lady is able to hold the handle of the pan with her barehands?
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1. The handle is made of good insulator of heat.2. The handle has low thermal conductivity.3. The handle has high thermal energy.
A. I and II only C. II and III only
B. I and III only D. I, II and III
273. A metal screw cap of a bottle will not turn when trying to remove it. It is placed under hot waterfor a few minutes. The metal cap then turns easily. This is due to the fact thatA. water is liquid C. matter contracts when cooled
B. the metal cap is solid D. matter expands when heated
274. Which of the following explains why the lady is able to hold the handle of the pan with her barehands?
1. The handle is made of good insulator of heat.2. The handle has low thermal conductivity.3. The handle has high thermal energy.
A. I and II only C. II and III only
B. I and III only D. I, II and III
275. Why are cooking utensils provided with wooden handles?A. wood is cheaper than steel
B. wood is light and easy to handle Electricity
C. wood is a poor conductor of heat
D. it move toward the lower elevation
276. Thermos bottle used to hold hot liquid for a long time. Which of the following parts of thethermos bottle conducts heat poorly?
A. stopper C. ceramic base
B. vacuum D. outer casing
277. Which of the following explains why the lady is able to hold the handle of the pan with her barehands?
1. The pan is made of good insulator of heat.2. The pan has low thermal conductivity.3. The handle has high thermal expansion.
A. I and II only C. II and III onlyB. I and III only D. I, II and III
278. Copper is a good conductor of heat and electricity. It classifies asA. insulators C. conductor
B. neutral D. charges
differentiates the three types of charges279. If you comb your hair and the comb becomes positively charged, what will happen to your hair?
A. It will remain uncharged.
B. It will be repelled by the comb.
C. It will become positively charged.
D. It will become negatively charged.
280. It is a positively charged particle.A. electron B. proton C. Neutron D. Neutral
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281. A charged object is brought near a metal ball that is mounted on a rubber sheet. If the metal ballacquired a negative charge of the object that was brought near it?
A. neutral
B. positive
C. negative
D. Cannot determine from the given information alone
282. Charges cannot be created nor destroyed, but can be transferred from one material to another.A. Law of Inertia C. Electrostatic Law
B. Law of Thermodynamics D. Law of Conversation of Change
283. A charged object is brought near a metal ball that is mounted on a rubber sheet. If the metal ballacquired a negative charge after it was grounded momentarily, what must be the charge of the
object that was brought near it?
A. neutral
B. positive
C. negative
D. Cannot determine from the given information alone
284. Positively charged means it lost some electrons while negatively charged has _____________.A. gained electron
B. lost electrons
C. both A and B
D. A only
285. There are three types of charges the positive, negative and neutral charges. What will happenedwhen two unlike charges like positive and negative are brought together?
A. they will repel each other
B. they will attract each other
C. they will neutralize each other
D. they will have no effect on each other
286. What will happen when two like charges are brought together?A. they will repel each other
B. they will attract each other
C. they will neutralize each otherD. they will have no effect on each other
287. Which among the three charges orbit around the nucleus and are negatively charge?A. protons B. electrons C. neutron D. none of the above
288. Which of the following describes the usual way by which a material can gain a positive charge?A. by gaining protons
B. by gaining electrons
C. by losing protons
D. by losing electrons
289. A charged object is brought near a metal ball that is mounted on a rubber sheet. If the metal ballacquired a negative charge after it was grounded momentarily, what must be the charge of the
object that was brought near it?
A. neutral
B. positive
C. negative
D. Cannot determine from the given
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290. Which statement best refers to Electrostatic Law?A. like charges repels and unlike charges attract
B. unlike charges repels and like charges attract
C. A and B
D. none of these
291. Which of the following can be attracted by a positively charges object?A. another positively charges object
B. any other object
C. a neutral object
D. no other object
292. It refers to uncharged charge.A. neutrons B. electrons C. proton D. all of the above
293. Which of the following is a positively charged ion?A. protons B. electrons C. neutron D. quartz
294. Atoms have electric charge inside them, the particles that carries positive charge is called A. electron B. protons C. neutron D. photons
demonstrates the different types of charging processes295. The figure shows three pairs of plate. The electrostatic force between the plates is shown for two
of the pairs. If B is negative, what is the charge of A? and what kind of force exists in the thirdpair?
A. negative, attractive C. positive, attractive
B. negative, repulsive D. positive, repulsive
296. Which of the following can be attracted by a positively charged object?A. Any other object C. Another positively charged object
B. A neutral object D. No other object
297. Which of the following exhibits charging y induction?A. Touching the sticky side of adhesive tape
B. Rubbing the balloon against your classmates wet hand
C. Touching the soft drink can which was placed near a charged balloon
D. Letting the charged softdrink can comes in contact with a neutral softdrink
can
298. If you comb your hair and the comb becomes positively charged, what will happen to your hair?A. it will be repelled by the comb
B. it will remain uncharged
C. it will become positively charged
D. it will become negatively charged
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299. The figure shows three pairs of plate. The electrostatic force between the plates is shown for twoof the pairs. If B is negative, what is the charge of A? and what kind of force exists in the third
pair?
A. negative, attractive C. positive, attractive
B. negative, repulsive D. positive, repulsive
300. The figure shows three pairs of plate. The electrostatic force between the plates is shown for twoof the pairs. If B is negative, what is the charge of A? and what kind of force exists in the third
pair?
A. negative, attractive C. positive, attractive
B. negative, repulsive D. positive, repulsive
301. Discharging is the process of removing excess charges on an object while grounding is a process ofproviding path between the charged object and the ground, what is the importance of grounding?
A. it can transfer electrons from or to charge object in order to neutralize it
B. it is necessary in electrical device and equipment so that it prevent the build uf excess charges where it is not needed.
C. it will add charges to the appliances
D. both A and C
302. Which of the following describes the usual way by which a material can gain a positive charge?A. by gaining protons
B. by gaining electrons
C. by losing protons
D. by losing electrons
303. If you comb your hair and the comb becomes positively charged, what will happen to your hair?A. it will be repelled by the comb
B. it will remain uncharged
C. it will become positively charged
D. it will become negatively charged
304. A neutral metal sphere is touched by a negatively charged metal rod. As a result, what will happento the metal sphere?
A. positive charged C. neutral
B. negative charged D. much more massive
305. Which of the following can be attracted by a positively charged object?A. another positively charged object C. a neutral object
B. any other object D. no other object
306. If you comb your hair and the comb becomes positively charged, what will happen to your hair?A. it will be repelled by the comb
B. it will remain uncharged
C. it will become positively charged
D. it will become negatively charged
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307. Which statement best describes the Law of Conservation of Charge?A. the total charge in a system is not constant
B. charges cannot be created nor destroyed, but can be transferred from one
material to another
C. the total charge in a system must remain constant
D. B and C
308. If you comb your hair and the comb becomes positively charged, what will happen to your hair?A. it will be repelled by the comb
B. it will remain uncharged
C. it will become positively charged
D. it will become negatively charged
309. Which of the following can be attracted by a positively charges object?A. another positively charges object
B. any other object
C. a neutral object
D. no other object
310. Atoms are the building blocks of matter and that the material objects are made up of atoms andcombination of atoms. Its presence provides electrical property. What type of charging process
happens when you rub two objects.
A. charging by induction
B. charging by convection
C. charging by conduction
D. charging by friction
311. When you pulled the tape vigorously from the table, some of the electrons from the tablessurface were transferred to the tape. This means that the table has lost some electrons so it has
become
A. negatively charged
B. positively charged
C. neutral
D. negative and positively charge
explains the importance of earthing or grounding312. A charged object is brought near a metal ball that is mounted on a rubber sheet. If the metal ball
acquired a negative charge of the object that was brought near it?
A. positive
B. negative
C. neutral
D. Cannot determine from the given information alone
313. Which of the following reasons explain why grounding is important for electrical devices likerefrigerator?
A. to neutralize the refrigerator
B. to save electricity
C. to hasten the frosting process
D. to make the refrigerator artistic
314. The process of removing excess charges on an object.A. discharging
B. lightning
C. grounding
D. polarization
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315. Any object that can serve as an unlimited source of electrons so that it will be capable ofremoving or transferring electrons from or to a charged object in order to neutralize that object.
A. ground C. neutralize
B. discharge D. charge
316. A charged object is brought near a metal ball that is mounted on a rubber sheet. If the metal ballacquired a negative charge after it was grounded momentarily, what must be the charge of theobject that was brought near it?
A. neutral
B. positive
C. negative
D. Cannot determine from the given information alone
317. Te following are importance of grounding or earthing in the electrical system EXCEPTA. provides a low resistance path to ground for any surges or lightning strikes
that may occur
B. provides a low resistance path to ground fir fault currents
C. prevent the build-up of excess charges from the system
D. keeps the electrical system fluctuate and malfunction
318. A negatively charged rod is brought near a metal can that rests on a wooden box. You touch theopposite side of the can momentarily with your finger. If you remove your finger before removing
the rod, what will happen to the can?
A. It will be discharged
B. Its charge will remain as it was
C. It will become positively charged
D. It will become negatively charged
319. Why is grounding important?A. it let electron attracted to the earth
B. it attracts charges from the ground
C. it retains the property of the charged body
D. it allows electrons to flow in any direction
320. Why is the process of grounding important?A. grounding is necessary in electrical devices and equipment since it canprevent the build-up of excess charges where it is not needed
B. grounding collects electricity needed to light a bulb.
C. A and B
D. none of these
321. A charged object is brought near a metal ball that is mounted on a rubber sheet. If the metal ballacquired a negative charge after it was grounded momentarily, what must be the charge of the
object that was brought near it?
A. neutral C. negativeB. positive D. cannot be determined from the given information
322. It is necessary in an electrical equipment and devices since it can prevent the buildup of excesscharges where is not needed.
A. grounding
B. charging
C. polarization
D. none of the above
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323. It is the process of removing excess charge on an object by means of transmitter of electronsbetween it and another object.
A. electrolysis
B. grounding
C. charging
D. conducting
324. A ground can be any object that serves as an unlimited source of electrons so that it will be ableto remove or transfer electrons from or to a charged object in order to neutralize that object. That
process may be referred as
A. charging
B. electricity
C. induction
D. grounding
describes how a lightning rod works325. A positively charged rod is brought near a metal can that rests on a wooden box. You touch the
opposite side of the can momentarily with your finger. If you remove your finger before removing
the rod, what will happen to the can?
A. It will be discharged
B. Its charge will remain as it was
C. It will become positively charged
D. It will become negatively charged
326. Lightning rods are placed at the top of a structure and must also be ground, why?A. when lightning strike the rod it will hit the building or structureB. lightning rods are not advisable to use because it attracts lightning
C. when lightning strikes the rods, the charges pass safety to the ground
D. lightning rods are non-conductors so it wont attract lightning
327. Which of the following is CORRECT?A. flat ironthermal energy to electrical energy
B. electric fanelectrical energy to mechanical energy
C. washing machinemechanical energy to electrical energy
D. flashlightlight energy to electrical energy
328. A negatively charged rod is brought near a metal can that rests on a wooden box. You touch theopposite side of the can momentarily with your finger. If you remove your finger before removing
the rod, what will happen to the can?
A. It will be discharged
B. Its charge will remain as it was
C. It will become positively charged
D. It will become negatively charged
329. Lighting occurs when the region of ___________________ comes close to the positive are of theearth.
A. cloud C. land
B. sky D. all of these
330. A negatively charged rod is brought near a metal can that rests on a wooden box. You touch theopposite side of the can momentarily with your finger. If you remove your finger before removing
the rod, what will happen to the can?
A. It will be discharged
B. Its charge will remain as it was
C. It will become positively charged
D. It will become negatively charged
8/13/2019 Grade 7 - science exam sets
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331. How do lightning rods work?A. It attempts to carry current away from the structure safely to ground
B. It allows the current to flow to ground without causing any heat damage
C. both A and B
D. neither A nor B
332. Is it possible to charge an electrical insulator?A. No, because they hinder charges from passing through them
B. No, because insulators have no free charges in them
C. Yes, because they can also conduct electricity
D. Yes, because electrons can be transferred between insulators through friction
333. A negatively charged rod is brought near a metal can that rests on a wooden box. You touch theopposite side of the can momentarily with your finger. If you remove your finger before removing
the rod, what will happen to the can?
A. It will be discharged
B. Its charge will remain as it was
C. It will become positively charged
D. It will become negatively charged
334. How do lightning rod works?A. a metal rod, used to protect building, is placed at a structure apex, is grounded
by a low resistance cable
B. the lightning strikes the rod and possess harmlessly into the ground, but the rodmust be high enough for lightning to strike at it, rather than the structure
C. the rods area of protection isa cone shape, with the base radius equal to theheight of the rod
D. all of these335. A negatively charged rod is brought near a metal can that rests on a wooden box. You touch the
opposite side of the can momentarily with your finger. If you remove your finger before removing
the rod, what will happen to the can?
A. It will be discharged
B. Its charge will remain as it was
C. It will become positively charged
D. It will become negatively charged
336. A negatively charged rod is brought near a metal can that rests on a wooden box. You touch theopposite side of the can momentarily with your finger. If you remove your finger before removingthe rod, what will happen to the can?
A. It will be discharged
B. Its charge will remain as it was
C. It will become positively charged
D. It will become negatively charged
337. Buildings are protected from lightning by providing them with metallic lightning rods extending toa ground from a point above the highest part of the roof. In this case, how does lightning rod
works?
A. the lightning rod reflects the lightning to space
B. the lightning rod absorbs the lightning within it
C. the lightning rod attracts the lightning into another direction
D. the lightning rod conducts the lightning to the ground
338. The charged acquired by the glass rod when it is rubbed with the silk is positive, since it gains anexcess of protons, the charge acquired by the silk cloth is
A. positive
B. negative
C. neutral
D. discharged