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A tennis player tosses a tennis ball straight up and then catches it after 1.34 s at the same height as the point of release.A. What is the acceleration of the ball while it is in flight? Find the initial velocity of the ball? Find the maximum height it reaches ?

User Eun Woo Song
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1 Answer

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So already, we know that the acceleration is going to be due to gravity, so it will always be 9.8 m/s/s downwards

For initial velocity, we will need to do kinematics to determine

We know that the acceleration = 9.8 m/s/s

time = 1.33 seconds

and since we know the ball will stop at the very peak of the arc, vf = 0

However, because the ball will have only traveled half way (since we are trying to find the path from initial thrown to the peak of the throw), we will need to divide time by half, and make time = .665 seconds

With these three, we can find max height (also the travel the ball goes) and the initial velocity.

For initial velocity, we can use the formula:

Vf = v0 + at

adjust for v0

v0 = vf - at

plug in what we know

v0 = 0 - (-9.8)(.665) = 6.517 m/s

Now we can solve for max height using

x = vf(t) - 1/2(a)(t^2)

Plug in what we know

x = 0 - 1/2(-9.8)(.665)^2 = 2.1669 meters

User Sps
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