1. According to Hooke's law, the force that a spring exerts depends on which one(s) of the following. Choose all that are correct.

A.Mass

B.Velocity

C.Stiffness

D.Acceleration

E.Displacement

2. Spring A and Spring B both have the same spring constant. Spring A is compressed, and Spring B is stretched. If Spring A is compressed by the same amount asSpring B is stretched, which spring exerts a larger magnitude force?

A.Both exert the same magnitude force.

B.Spring B

C. Spring A

D.It cannot be determined because the sign of the spring forces changes depending on whether it is compressed or stretched.

3. Object A that is attached to Spring 1 follows a simple harmonic motion. Object B that is attached to Spring 2 also follows a simple harmonic motion. The spring constant of Spring 1 is the same as that of Spring 2. If the mass of Object A is smaller than that of Object B, choose the correct statement about the frequency of Object A (f_A) and the frequency of Object B (f_B).

A. f_Ais larger thanf_B

B. f_Ais the same asf_B

C.It does not have enough information to determine which frequency is larger.

D. f_Ais smaller thanf_B

4. When an ambulance is moving toward you with sirens on, choose the correct statement about the frequency of the sirens you hear if you are not moving.

A.The frequency you hear is higher than the original frequency of the sirens.

B.The frequency you hear is lower than the original frequency of the sirens.

C.The frequency you hear is the same as the original frequency of the sirens.

D.It does not have enough information to determine if the frequency you hear is higher or lower than the original frequency of the sirens.

5.By how many centimeters is a spring withk= 685 N/m compressed when F = 25 N is applied to compress it? Be careful with units.

6.When a spring with spring constant k = 816 N/m is compressed by x = 3.7 cm, what is the elastic potential energy stored in the spring in the unit of J? Be careful with units.

7. What is the frequency of a wave in Hz that propagates at the speed of 59 m/s with the wavelength of 1.76 m?

8. The acoustic impedance of fat isZ_fat= 1330000 kg/(m²s), and that of muscle isZ_muscle= 1710000 kg/(m²s). What proportion of the energy of a sound wave propagating in fat will betransmittedat the fat-muscle boundary?

9. A sound source produces a sound with frequency f = 882 Hz and is moving at the speed of v = 15.4 m/s. What is the frequency of the sound that a stationary observer hears when the sound source is moving away from the stationary observer? Use c = 329 m/s for the speed of sound in air.

10. A sound source produces a sound with frequency f = 792 Hz and is moving at the speed of v₁ = 14.3 m/s. An observer is moving at the speed of v₂ = 19 m/s. What is the frequency of the sound that the observer hears when the sound source is moving toward the observer, but the observer is moving away from the sound source? Use c = 310 m/s for the speed of sound in air.