How High and How Long Does a Volleyball Go When Hit Upwards?

AI Thread Summary
The discussion focuses on calculating the maximum height and time taken for a volleyball hit upwards from a height of 0.8m with an initial velocity of 7.5m/s. Participants suggest using the equations of motion, specifically d = vit + 1/2 at^2 and vf = vi + at, to solve the problem. There is uncertainty about correctly applying these equations, particularly in relation to the hint that the final velocity at maximum height is 0m/s. Attempts to calculate the height using vf^2 = vi^2 + 2ad are also mentioned, indicating a need for clarification on the approach. The conversation emphasizes the importance of understanding kinematic equations in solving projectile motion problems.
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Homework Statement



Stephanie hits a volleyball from a height of 0.8m and gives it an initial velocity of 7.5m/s straight up.?
a. how high will the volleyball go?
b. how long will it take the ball to reach its maximum height? (hint:@ max height, v= 0m/s)

Homework Equations



im not sure but maybe d=vit+1/2 at^2

The Attempt at a Solution



tried a lot of things :/
 
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d=vit+1/2 at^2 is good, but you also need v = vi + a*t so you can take advantage of that hint about the v being zero at maximum height.
 
Show your attempts.
 
tyvm! i think you use vf=vi+at to find how high it will go ?
 
rl.bhat said:
Show your attempts.

i did vf^2= 7.5^2+2(-9.81)(.8)
im not sure if its how you do this
 
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