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Sorry to bother with this stupid question, but I was hoping for some clarification.
Problem: A box starts from rest and slides down 40m down a frictionless inclined plane. The total vertical displacement of the box is 20m. How long does it take for the block to reach the end of the plane?
Answer: 4s
I understand how to get the answer if I take the x direction as mgsintheta (going down the plane), but my question is... why can't I solve the problem using the y displacement and the constant acceleration equation?
For example: y(final) - y(initial) = v(initial)t + 0.5at^2
-20 = (0.5)(-10)t^2
The answer I get using this method would be t=2s. What did I do wrong here?
Problem: A box starts from rest and slides down 40m down a frictionless inclined plane. The total vertical displacement of the box is 20m. How long does it take for the block to reach the end of the plane?
Answer: 4s
I understand how to get the answer if I take the x direction as mgsintheta (going down the plane), but my question is... why can't I solve the problem using the y displacement and the constant acceleration equation?
For example: y(final) - y(initial) = v(initial)t + 0.5at^2
-20 = (0.5)(-10)t^2
The answer I get using this method would be t=2s. What did I do wrong here?