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3 years ago

(c) The ball leaves the tennis player's racket at a speed of 50 m/s and travels a

Physics

1 answer:

Mazyrski [523]3 years ago

6 0

Answer:

t=0.417s

Explanation:

After the ball hits the racket it is in freefall(assume air resistance as negligible)

so a=-g

use

x-x0=v0t+1/2at^2

Plug in givens

20=50t-4.9t^2

Solve quadratic equation using quadratic formula

t= 0.417 seconds, (the other answer is extraneous because it is too big because in 1 second, the ball travels 50 meters)

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