How Long Does It Take for a Wall to Pass a Train Window?

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To determine how long it takes for the upper edge of a wall to pass a train window, the horizontal distance traveled by the wall must be calculated, which requires understanding the geometry of the situation. The wall slopes upward at a 12-degree angle, meaning the total horizontal distance is greater than the window's width of 2.0 m. Trigonometry is necessary to find this distance accurately. The time can then be calculated by dividing the total horizontal distance by the train's speed of 3.0 m/s. Properly visualizing the scenario with diagrams can aid in solving the problem correctly.
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Homework Statement


You are on a train that is traveling 3.0 m/s (to the left direction) along a level straight track. very near and parallel to the track is a wall that slopes upward at a 12 degree angle with the horizontal. As you face the windoes (.90 m high), (2.0 m wide) in your compartment, the train is moving to the left. The top edge of the wall 1st appears at window corner A and eventually disappears at window corner A and eventually disappears
at window corner B. How much time passes between appearance and disappearance of the upper edge of the wall.

Homework Equations


Time= distance/average speed


The Attempt at a Solution



I multiplied .90 and 2.0 and I got .18m and then I divided it by 3.0 and I got .06 s. This is way off. What do I need to do.
 
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Why did you multiply the lengths?

You need to find the horizontal distance travelled... draw a picture... how do the window and wall look right as the wall appears... and draw another picture right when the wall leaves...

What is the total horizontal distance? Hint: it is more than 2.0m. you'll need a little trig. Once you get the distance, divide by velocity to get time.
 
?? Even your multiplication is wrong: if the window has width 2.0 m and height 0.9 m, then it has area 1.8 m2- but that has nothing to do with the problem.
 
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