BR Physics Circular Motion q.14

[shahcoco]

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If you have the book, p. 101 #14

How long will it take the ball in Experiment 2* to reach the ground if it were released at point A (closest to center of axis) will a speed of sqrt2gL?

The answer sets up delta y = 1/2gt^2 = 2L and solves for t

I understand the 1/2gt^2 part, but where did 2L come from? It must be related to the speed but I can't see how exactly...

*Experiment 2 = student takes a ball and string and swings the ball in a vertical circle such that the ball nearly hits the floor

 

[sazerac]

When the ball is released (with no vertical velocity), how high off the ground is it?

 

[shahcoco]

When the ball is released (with no vertical velocity), how high off the ground is it?

OH. It's at the top of the diagram! Thanks :] Got confused by looking at the wrong figure.