# Traveling wave Snapshot

1. Jan 13, 2014

### BMcC

The graph shows a snapshot of a travelling harmonic wave; eight points are indicated. Answer the five questions by selecting from the choices below

a) ←
b) →
c) ↑
d) ↓
e) The velocity is zero

1.If the wave is moving to the right, what is the direction of the velocity of the particle at point 5?
2.If the wave is moving to the left, what is the direction of the velocity of the particle at point 4?
3.If the velocity of the particle at point 5 is given by the arrow C, in which direction is the wave moving?
4.If the velocity of the particle at point 2 is given by the arrow D, in which direction is the wave moving?
5.If the wave is moving in the direction A, what is the direction of the velocity of the particle at point 8?

My thought process

1. If the wave is moving to the right, the velocity of the particle must also be moving in that direction, so B

2. If the wave is moving to the left, the velocity of the particle must also be in that direction, so A

3. If the velocity of particle 5 is up, then the direction the wave is moving is up? I'm not very sure about this one but put C

4. Same goes for this one. I put D

5. For this one I am also not quite sure.

Thanks in advance, I missed the class where we talked about traveling waves and I'm struggling with this question!

2. Jan 13, 2014

### Simon Bridge

3. Jan 13, 2014

### consciousness

From the definition of waves, they transfer energy, not particles. The particles keep oscillating about their mean position.
This problem can be solved qualitatively. Just imagine the wave a short time after this snapshot. Where do the particles go?