1 While in your back yard Jack decides to perform a physics

1. While in your back yard, Jack decides to perform a physics experiment involving waves. He ties one end of the rope to a tree, then Jill holds the other end keeping tension on the rope. Jill wiggles the rope up and down and you watch the wave propagate toward the tree. Later, Jill wiggles the rope up and down faster than before, but decreases the tension in the rope (keeping all other quantities the same). How does the wave speed of the second wave compare to the wave speed of the first wave she generated? Select One of the Following: (a) The wave speed is faster for the second wave. (b) The wave speed is slower for the second wave. (c) The wave speed can be the same for both waves if she wiggles it fast enough to make up for the reduction in tension.

2. What best describes the motion of the particles in the medium for a transverse wave? Select One of the Following: (a) In a transverse wave the particles in the medium move back and forth along the direction the wave is traveling. (b) In a transverse wave the particles in the medium move consistently in the direction the wave is traveling. (c) In a transverse wave the particles in the medium move back and forth perpendicular to the direction the wave is traveling. (d) In a transverse wave the particles in the medium move consistently outward in a direction perpendicular to the direction the wave is traveling.

3. Which of the following is true? Select One of the Following: (a) Waves transmit momentum, but not energy. (b) Waves transmit energy, but not momentum. (c) Waves transmit energy and momentum. (d) Waves transmit neither energy nor momentum.

I got BDC but one of these is wrong and i don\'t know which one

Solution

The first two are correct. As speed of a transverse wave is proportional to square root of tension in the string, speed reduces. So, option B is correct. For transverese waves, particles oscillate in the direction perpendicular to the direction of propagation of the wave. So, C is correct. As, particles on the string do not move in the direction of propagation of the wave, waves transfer energy but not momentum. So, option B is correct.