1. The problem statement, all variables and given/known data These are two problems, but what I'm supposed to do is the same. The general case is that i'm given two Y[m] vs. t, 2 Y[m] vs. x[m], or a Y[m] vs. x[m] and Y[m] vs. t graph. It asks me to explain how the y(t) graphs tell you "whether this wave is moving left or right." How would it been done in case? I just need a general method that I can apply because the way i've had it explained before was really unclear Note these are for two different problems Graph set #1: two Y[m] vs. t Graph set #2: a y[m] vs. x[m] and a Y[m] vs. t 2. Relevant equations Y=Asin(2∏/T*t±2∏/λ*x+phi) 3. The attempt at a solution For graph set #1 (the first problem): I looked at the graphs and noticed that second one's position is .1ms away from the first and noticed that if you shift the first graph over to the left it looks like the second graph. Does that mean it's going left? For graph set #2 (the second problem): I looked at the y(t) vs. t graph and noticed that it's going down originally and realized that if i shifted the graph to the right (y(x) vs. x(t)) at point x=0 I would get the same graph, so it must be going left? I dont understand this at all. Also what if I had two y(x) vs. x graphs. What would happen then?