What is the impulse given the wall?

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The discussion revolves around calculating the impulse given to a wall by a tennis ball striking it at an angle. The ball has a mass of 0.045 kg and strikes the wall at 25 m/s, rebounding at the same speed and angle. The impulse is calculated using the formula I = (pf - pi)/t, where pf and pi represent final and initial momentum, respectively. The initial calculation yields an impulse of 2.25, although the expected answer is 2.1, indicating a need for clarification on the components of momentum contributing to the impulse. Understanding the perpendicular components of momentum is crucial for accurate calculations in this context.
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Homework Statement



A tennis ball of with a mass of .045 kg and speed of 25 m/sec strikes a wall at an angle of 45 degrees and rebounds with the same spped at 45 degrees. What is the impulse given the wall?

Homework Equations



I= pf-pi/t

The Attempt at a Solution



I= mv-mv/t
(.045)(25)-(-.045)(25)/1
1.125-1.125/1
I=2.25
I know the answer is 2.1, but don't know how to get it.
 
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RUNVS said:

Homework Equations



I= pf-pi/t

What do the letters stand for in this equation?
 
The letters stand for Impulse = final momentum - the initial momentum/ time
 
the impulse is the change in momentum. So the equation is
change in momentum = (change in force) / time
if I'm not mistaken.
 
Another way of writing it is:

Impulse = Force x time = change in momentum
 

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