2. QuickCheck 14.4
A block oscillates on a very long horizontal spring. The graph shows the block’s kinetic energy as a function of position. What is the spring constant?
1 N/m
2 N/m
4 N/m
8 N/m
Answer: C
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3. QuickCheck 14.8
A block of mass m oscillates on a horizontal spring with period T  2.0 s. If a second identical block is glued to the top of the first block, the new period will be
1.0 s
1.4 s
2.0 s
2.8 s
4.0 s
Answer: D
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4. QuickCheck 14.12
A mass oscillates up and down on a spring; the motion is illustrated at right.
At which time or times shown is the acceleration zero?
At which time or times shown is the kinetic energy a maximum?
At which time or times shown is the potential energy a maximum?
Answers: 1: A, C, E
2: A, C, E
3: B, D
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5. QuickCheck 14.15
A pendulum is pulled to the side and released. The mass swings to the right as shown. The diagram shows positions for half of a complete oscillation.
At which point or points is the speed the highest?
At which point or points is the acceleration the greatest?
At which point or points is the restoring force the greatest?
Answers: 1: C
2: A, E
3: A, E
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6. QuickCheck 15.8 For this sinusoidal wave, what is the amplitude? 0.5 m
Answer: C
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7. QuickCheck 15.9 For this sinusoidal wave, what is the wavelength?
0.5 m
1 m
2 m
4 m
Answer: C
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8. QuickCheck 16.1
Two wave pulses on a string approach each other at speeds of 1 m/s. How does the string look at t = 3 s?
Answer: C
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9. QuickCheck 16.4 What is the wavelength of this standing wave? 0.25 m
Standing waves don’t have a wavelength.
Answer: C
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10. QuickCheck 16.9
An open-closed tube of air of length L has the closed end on the right. Which graph shows the 3 rd harmonic standing wave in this tube?
Answer: C
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11. Answers
Slide: N/m s ) A, C, E 2.) A, C, E 3.) B, D C 2. A, E 3. A, E m 15.9 – 2 M C 16.4 – C C