Collisions, Impulse, and Reference Frames

AI Thread Summary
The discussion revolves around a racquet ball's collision with a wall, focusing on calculating momentum and forces involved. The initial momentum of the ball is established at 3.773 kg·m/s. Participants highlight the need to analyze the momentum change in terms of horizontal and vertical components due to the angle of impact. The average force exerted by the wall is derived from the impulse-momentum theorem, considering the time of contact. The conversation concludes with a participant expressing gratitude for the clarification on how to approach the problem.
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A racquet ball with mass m = 0.245 kg is moving toward the wall at v = 15.4 m/s and at an angle of θ = 28° with respect to the horizontal. The ball makes a perfectly elastic collision with the solid, frictionless wall and rebounds at the same angle with respect to the horizontal. The ball is in contact with the wall for t = 0.069 s.


What is the magnitude of the initial momentum of the racquet ball?
What is the magnitude of the change in momentum of the racquet ball?
What is the magnitude of the average force the wall exerts on the racquet ball?

I've already computed the initial momentum =3.773kgm/s but I honestly can't figure out the second question...
I'm using Favg*delta(t) equals impulse but I can't figure it out
Please help me!
 
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Since, it's hitting the wall at an angle, you'll have to think of it in terms of components. If the wall is vertical, then the object is either moving up or down with some horizontal velocity when it hits it. Think about how the horizontal and vertical components of velocity will change, and thus how the components of momentum will change.
 
Ahhhh! Got it! Thank you so much!
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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