14.  As a tennis ball is struck, it departs from the racket horizontally with a speed of 28.0 m/s. The ball hits the court at a horizontal distance of 19.6 m from the racket. How far above the court is the tennis ball when it leaves the racket?

We are assuming no air resistance which is why there is no acceleration in the x direction.  We can use the x direction information to find the time of flight and then use that to find the initial height.

Rearrange we find time of flight

 

 

Since all the vertical motion is downward we can leave it positive.  Plug in for t

 

 

Alternatively we could have done more algebra before plugging in numbers

 

 

 

 

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This page last updated on January 11, 2020