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Lanier Physics Spring Final Breakdown
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These questions come from a question generator that aligns with these textbook sections. Here is the breakdown.
Section/# of questions/Description
Kinematics 8 questions
3‐1 1 finding displacement
3‐2 4 Speed and velocity definitions, graphs, and equations
4‐1 2 acceleration graphs and equations
4‐2 1 gravity and freefall numeric
Forces 7 questions
5‐1 2 force equation, mass vs weight (a = g = 9.8 m/s2)
5‐2 3 force equation
7‐2 2 Newton’s Law of Universal Gravitation, proportionality and equation
Work/Energy/Power 7 questions
9‐1 4 work, gravitational potential energy, kinetic energy equations
9‐2 1 power equation
10‐1 1 Conservation of energy, gravitational potential energy to kinetic energy, predict velocity
10‐2 1 conservation of energy
Momentum/Impulse 5 questions
11‐1 3 impulse formula, momentum formula
11‐2 2 conservation of momentum formula, predict velocity
Waves 7 questions
15‐1 3 Comparing wavelength, wavespeed equations, characteristics of waves
15‐2 3 wave characteristics during boundary interactions
15‐3 1 wave superposition, predict resulting wave
Electricity and Circuits 6 questions
17‐1 1 determine correct description of voltage source
17‐2 1 Ohm’s Law
17‐3 4 equivalent resistance and Ohm’s Law
WAVES
1. Which graph shows the longest wavelength?
A. B. C.
Solution: The wavelength is the distance between successive peaks of the wave. Figure B has the longest (horizontal) distance between successive peaks, so it has the longest wavelength.
2. How is it that you can hear people inside another room even when the door is only opened very slightly?
Solution: When the sound waves exit through the crack in the door, they diffract, allowing them to bend and spread out around the crack.
3. Label the diagrams as reflection, refraction, or diffraction?
Solution: Diffraction reflection refraction
4. What characteristic of waves remains unchanged when a wave refracts?
Solution: The frequency of a wave is unchanged by refraction. Wavelength, speed, amplitude, energy, polarization, and direction are all typically changed by refraction from one media into another.
5. Two waves of the same frequency and wavelength interfere with each other. The first wave has amplitude A1 = 41 cm and wavelength λ1 = 3 m. The second wave has amplitude A2 = 52 cm and wavelength λ2 = 3 m. What is the amplitude of the sum of the two waves if the waves are exactly in phase?
Solution: Since the waves are in phase, they will undergo constructive interference and so the amplitude of the resulting wave is the sum of the amplitudes of the two waves: A=A1+A2=41 cm+52 cm= 93.0 cm
6. A water wave has a frequency of 2 Hz and a wavelength of 1.5 m. What is the speed at
which this wave travels?
Solution:
v = (2Hz)( 1.5m)
v = 3.0 m/s
7. Describe the difference between transverse and longitudinal waves. Give examples of
each.
Solution: Transverse waves transfer energy in a direction perpendicular to the direction of the disturbance in the medium. A vibrating string and electromagnetic waves, such as light, are examples of a transverse wave. Longitudinal waves are waves that transfer energy in the same direction as the disturbance in the medium. Sound waves are examples of longitudinal waves. MOMENTUM
1. A sprinter has a mass of 60 kg and is running at a velocity of 8.0 m/s around the
track. How much momentum does she have?
Solution: p=mv p= (60kg)(8.0 m/s) p= 480 kg m/s
2. May (67 kg) and Amber (53 kg) stand motionless on ice skates, facing each other at arm's length on a smooth, frozen pond. Which of the following actions will give Amber the least speed?
a. May pushes Amber with 30N of force for 0.8 second b. May pushes Amber with 60N of force for 0.2 second c. Amber pushes May with 100N of force for 0.05 second d. Amber pushes May with 200N of force for 0.1 second
Solution: The correct answer is c. Looking at impulse for this situation, we have that J = Δp = mΔv = FΔt. Since Amber is motionless in the beginning, her final speed is v = FΔt⁄m. Because Amber's mass does not change, the smallest product of force and time will give her the least speed. 3. Two boys stand facing each other on their skateboards. What way will the boys roll
(if at all) if they put their arms out straight and one pushes against the other’s hands? Solution: The boys will roll on their skateboards in opposite directions.
4. A 62.0 kg curler runs into a 78.1 kg curler are traveling toward each other at the same speed. They bounces off one another and the 62.0 kg curler moves away at 1.29 m/s. What was the new velocity of the 78.1 kg curler?
Solution: M1V1= M2V2 (62)(1.29) = (78.1) V2 79.98 = (78.1) V2
-1.02 m/s = V2
Once the curlers bounce off one another, they travel in opposite directions to give a sum of zero.
5. What is the change in momentum of a cyclist who stops his bike with a force of 450N
in 15 seconds?
Solution: F = p t 450 = p 15 6750= p