HORIZON INTERNATIONAL BILINGUAL SCHOOL name: 2. TERM, 1. EXAMINATION PHYSICS 7th Grade Surname:

a.What statements are True (T) and False (F)? Choose.

1. Only objects that are moving have energy. …………. 2. Energy of motion depends only on the object’s mass and speed. ……… 3. Energy changes from one form to another when a ball is thrown upward. …………… 4. Living organisms change chemical energy to thermal energy. ……….. 5. The total amount of energy increases when a candle burns. ………….. 6. Solar energy is the least expensive energy source. ……………… 7. Energy is the ability to cause change. ……………. 8. The law of conservation of energy states that energy cannot be created or destroyed. …………….

1. Objects that are able to fall have what type of energy? A) kinetic B) potential C) radiant D) electrical

2. Which form of energy does light have? A) electrical B) kinetic C) nuclear D) radiant

3.Muscles perform what type of energy transformation?

A) kinetic to potential B) kinetic to electrical C) thermal to radiant D) chemical to kinetic

4. Photovoltaics perform what type of energy transformation?

A) thermal to radiant B) kinetic to electrical C) ra diant to electrical D) electrical to thermal

5.The form of energy that food contains is which of the following?

A) chemical C) radiant B) potential D) electrical

6.Solar energy, wind, and geothermal are what type of energy

resource?

A) inexhaustible B) nonrenewable C) inexpensive D) chemical

7. Which of the following is a nonrenewable source of energy?

A) hydroelectricity B) nuclear C) wind D) solar

8. A generator is NOT required to generate electrical energy when

which of the following energy sources is used?

A) solar C) hydroelectric B) wind D) nuclear

9. Which of the following are fossil fuels? A) gas B) oil C) coal D) all of these

10.Almost all of the energy that is used on Earth’s surface comes from

which of the following energy sources?

A) radioactivity B) chemicals C) the Sun D) wind

11. What occurs when energy is transferred from one object to

another?

A) an explosion B) a chemical reaction C) nuclear fusion D) a change

12) For which of the following is kinetic energy converted into potential

energy?

A) a boulder rolls down a hill B) a ball is thrown upward C) a swing comes to a stop D) a bowling ball rolls horizontally

13) The gravitational potential energy of an object changes when which

of the follow-ing changes?

A) the object’s speed B) the object’s mass C) the object’s temperature D) the object’s length

14) Friction causes mechanical energy to be transformed into which of

these forms?

A) thermal energy C) kinetic B) nuclear energy D) potential

15) The kinetic energy of an object changes when which of the

following changes?

A) the object’s chemical potential energy B) the object’s volume C) the object’s direction of motion D) the object’s speed

16) When an energy change occurs, which of the following is true?

A) Mechanical energy doesn’t change. B) Mechanical energy is lost.

C) The total energy doesn’t change. D) Mass is converted into energy.

17) Which of the following describes the energy conversions in a car’s

engine?

A. chemical to thermal to mechanical B. chemical to electrical to mechanical C. thermal to mechanical to chemical D. kinetic to potential to mechanical

18) What is the SI unit of energy?

a) Newton(N) b) Kilogram (kg) c) Joule(J) d) meter (m) e) ampere(A)

19) The main difference between kinetic energy and potential energy is that a. kinetic energy involves position, and potential energy involves motion. b. kinetic energy involves motion, and potential energy involves position. c. although both energies involve motion, only kinetic energy involves position. d. although both energies involve position, only potential energy involves motion.

20) What sector of our society consumes the most energy?

a. transport b. commerce c. residential d. industry

21) Most energy conversions produce …

a. motion b. sound c. heat d. light

22) Write down three forms of energy which the apple on the right has.

23) Use the graph below to answer questions

i. According to the graph above, in which year will global oil production

be at a maximum? A. 1974 C. 2010 B. 2002 D. 2050

ii. Approximately how many times greater was oil production in 1970

than oil production in 1950?

A. 2 times C. 6 times B. 10 times D. 3 times

iii. In which year will the production of oil be equal to the oil

production in 1970? A. 2010 C. 2022 B. 2015 D. 2028

24) Complete the following concept map on energy.

25) Explain what means energy is conserved and is transformed.

26) The graph below shows how the Kinetic Energy of Falling Rock changes with time. Use it to answer the following 4 questions a) According to the graph, which of the following is the best estimate for the kinetic energy of the rock after it has fallen for 1 s? A. 100 J B. 200 J C. 50 J D. 0 J b) According to the graph, what is the potential energy of the rock before it fell? A. 400 J B. 200 J C. 800 J D. 0 J c) After 2 seconds, how much kinetic energy does the rock have? A. 400 J B. 200 J C. 800 J D. 0 J d) After 2 seconds, how much potential energy does it have? A. 400 J B. 200 J C. 800 J D. 0 J

27) A 1000-kg roller coaster car starts from rest at point A on a

frictionless track, shown in figure below.

a) At which point on the track is the car’s potential energy the greatest?

the least?

b) At which point on the track is the car’s kinetic energy the greatest?

the least?

28) The diagram below shows a pendulum which was released from

position A.

What form(s) of energy did the pendulum have at (i)A, (ii)B, (iii)C?