A ball rolls off a horizontal table at 0.43 m/s and strikes the ground 0.20 m horizontally from the base of the table. How high is the table?

Question

A ball rolls off a horizontal table at 0.43 m/s and strikes the ground 0.20 m horizontally from the base of the table.  How high is the table?

whpalmer4 · Answer

The horizontal component of the ball's motion lasts for the amount of time it takes to go 0.20 m when travelling at 0.43 m/s.  Using $d=rt$, find $t$.  Now use that value of $t$ in the formula for the distance traveled by a falling object under the influence of gravity to find the height of the table — it will be the distance the ball travels in that amount of time.