How Is Impulse Calculated in Tennis Ball Physics?

AI Thread Summary
Impulse in tennis ball physics is calculated using the change in momentum, which is derived from the ball's mass and its final velocity after being hit. In this scenario, the 58.0g ball reaches a height of 5.50m, indicating it gains gravitational potential energy, which can be converted to find its final speed of approximately 10.38 m/s. The initial momentum of the ball is zero since it was stationary, while the final momentum, calculated using the formula p=mv, results in 0.602 kgm/s. This value represents the impulse imparted by the racket to the ball during the hit. Understanding the relationship between energy conservation and momentum is key to solving such physics problems.
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Homework Statement


To warm up for a match, a tennis player hits the 58.0g ball vertically with her racket.
If the ball is stationary just before it is hit and goes 5.50m high, what impulse did she impart to it?

I know that the answer is 0.602 kgm/s but I don't understand why this is the answer

Homework Equations


P=mv

ptotal = Pinitial + Pfinal

The Attempt at a Solution


Pinitial = (0.058kg)(0 m/s)
= 0

Pfinal = (0.058kg)(vfinal

I'm not sure where to go from here.
I think that kinitial+Uinitial = kfinal+ufinal has something to do with it
But I'm not sure.
 
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Energy is conserved. If the ball reaches a height of 5.50 m, it has gained a certain amount of gravitational potential energy (you can calculate the amount). That energy had to come from somewhere. From this fact, you can deduce the speed of the ball at the end of the impact with the racket. ;)
 
compute v(0) tennis ball: v(t)[/2] = v(0)[/2] - 2*g*d → 0 = v(0)[/2] - 2*9.8*5.5 = 10.38 m/s.

ƩP(initial) = ƩP(final) (just before and just after the hit). In general p=mv.

Initial m(b)*v(b) + m(r)*v(r) = 0+ m(r)*v(r)

Final m(b)*v(b) + m(r)*v(r) = 0.058*10.38=0.602 kgm/s

So initial momentum racket is 0,602 kgm/s.
 
Fredb, we do NOT provide complete solutions to homework problems on this site. It is against site rules.
 
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