Why is the wave point moving in direction B instead of D?

[Cici2017]

Homework Statement

Homework Equations

The Attempt at a Solution

the point is going down the wave, so shouldn't the answer be D? Why is it B? Thank you! [/B]

 

[CWatters]

Look at the wave crests, they are moving to the right. What happens "next" at that point depends on what is just to the left of the point.

PS The point doesn't move down the wave. The wave moves past the point.

 

[Cici2017]

What happens "next" at that point depends on what is just to the left of the point.

Can you please explain this more? I don't get it ~ Thank you!

 

[CWatters]

Try this...
Print out the drawing.
Draw the wave shifted to the right about 1/4" or 5mm.
Mark on it the new position of the point
If possible post your sketch here.

 

[Cici2017]

Try this...
Print out the drawing.
Draw the wave shifted to the right about 1/4" or 5mm.
Mark on it the new position of the point
If possible post your sketch here.

ahh~ I think I got it. the new position of the point is higher than the old position, so the direction is up. Am I right?

 

[CWatters]

Correct.