You are on a train that is traveling at 3.0m/s along a level straight track. Very near and parallel to the tra

Question

track* is a wall that slopes upward at a 12 degress angle with the horizontal. As you face the window (o.9m high, 2.0m wide) in your compartment, the train is moving to the left, as the rawing indicates. The top edge of the wall appears at window corner. The top edge of the wall first appears at a window corner A and eventually disappears at window corner B. How much time passes betwen appearance and disapppearance of the upper edge of the wall?

Answer 1

Without the drawing that is obviously required to be sure, I'll assume that there is no distance between the wall and the window, so what you see relative to the window is actually the height change of the wall. The first corner is the forward bottom corner and the last one is the rearward top corner. The vertical height change
deltaH = 0.9 + 2.0*tan(theta)
The horizontal distance traveled
x = deltaH/tan(theta)
The time taken
t = x/v