Question

2. A ball of negligible size and a given mass is attached to a vertical spring that obeys Hooke's law. At equilibrium, its position and gravitational potential energy is chosen to be "zero". The mass is set in oscillation in a vertical direction. At what point during the oscillation will the ball-earth-spring system have the most negative gravitational potential energy?

A. The gravitational potential energy will be the most negative at its lowest position from the earth.

B. The gravitational potential energy can be zero but will never be negative.

C. The gravitational potential energy will be the most negative at both the highest position and lowest position from the earth.

D. The gravitational potential energy will be the most negative when the system stops moving.

E. The gravitational potential energy will be the most negative at its highest position from the earth.

3. Why doesn't the spring in a typical mountain bike shock absorber continue to vibrate (bounce up and down) after a rider hits a bump?

A. Because it converts the spring's elastic potential energy into gravitational potential energy.

B. Because it converts the spring's elastic potential energy into internal energy of damping oil.

C. Because it converts the spring's elastic potential energy into kinetic energy of the rider.

D. Because it converts the elastic potential energy in the spring on one side of the bike to elastic potential energy in the spring on the other side of the bike.

E. Because the spring in a mountain bike shock absorber is specially designed so that it never has any elastic potential energy.

4. Which of the descriptions below is an example of resonant energy transfer? (Choose all that are correct.)

A. A box is pushed with a constant force down an empty abandoned hallway and its speed increase.

B. A vibrating pendulum connected to a very similar second pendulum influences the vibration of the second pendulum. The amplitude of vibration of the first pendulum decreases and the amplitude of the second increases. This exchange of amplitude and energy keeps happening back and forth between the two pendulums.

C. Ultrasound machines are used to apply a variable force at a frequency that matches the natural frequency of gall stones, causing the gall stones to vibrate and break up.

D. Soldiers marching in unison on a bridge with their steps at a frequency that is very differentthan the natural vibration frequency of the bridge.

E. A block sliding on a horizontal surface slows down and comes to a stop due to the friction force.

5. In a longitudinal wave...

A. the vibrational motion of the particles is parallel to the direction of propagation of the disturbance.

B. the vibrational motion of the particles is due to the expansion and contraction of the atoms that make up the particles

C. the vibrational motion of the particles is faster in the surface of the medium than the inside of the medium.

D. the vibrational motion of the particles is perpendicular to the direction of propagation of the disturbance.

E. the vibrational motion of the particles is constantly alternating between its electric and magnetic fields.

6. In transverse waves...

A. the vibrational motion of the particles is due to the expansion and contraction of the atoms that make up the particles

B. the vibrational motion of the particles is faster in the surface of the medium than the inside of the medium.

C. the vibrational motion of the particles is perpendicular to the direction of propagation of the disturbance.

D. the vibrational motion of the particles is constantly alternating between its electric and magnetic fields.

E. the vibrational motion of the particles is parallel to the direction of propagation of the disturbance.

Answer 1

2) A. The gravitational potential energy will be the most negative at its lowest position from the earth.

3) A. Because it converts the spring's elastic potential energy into gravitational potential energy.

4) B. A vibrating pendulum connected to a very similar second pendulum influences the vibration of the second pendulum. The amplitude of vibration of the first pendulum decreases and the amplitude of the second increases. This exchange of amplitude and energy keeps happening back and forth between the two pendulums.

5) A. the vibrational motion of the particles is parallel to the direction of propagation of the disturbance.

6) C. the vibrational motion of the particles is perpendicular to the direction of propagation of the disturbance.