What is the magnitudue of the force acted on the ball

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The discussion focuses on calculating the force exerted on a 536 g ball that strikes a wall at 15.8 m/s and rebounds at 13.1 m/s, with contact lasting 0.038 seconds. Participants initially used the formula F=ma to find the force based on initial and final velocities, resulting in a force of approximately 407.642 N. However, they expressed confusion about the underlying principles behind their calculations. An explanation was provided referencing Newton's second law, emphasizing that force is the rate of change of momentum, which can be related to time. Understanding this concept clarifies the relationship between force, momentum, and time during the collision.
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A 536 g ball stricks a wall at 15.8 m/s and rebounds at 13.1 m/s. The ball is in contact with the wall for 0.038 s.

What is the magnitudue of the force acted on the ball during the collision?
 
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Hi knelson! :smile:

Show us what you've tried, and where you're stuck, and then we'll know how to help. :wink:
 


Well we (me and the girl who are studying together) we have the answer... and we can get the answer but we don't understand why.

We used F=ma to find the force using the initial velocity and did the same thing using the second velocity and added them together. We come up with the correct answer but we don't understand why.
 


It's 407.642
 
knelson said:
Well we (me and the girl who are studying together) we have the answer... and we can get the answer but we don't understand why.

We used F=ma to find the force using the initial velocity and did the same thing using the second velocity and added them together. We come up with the correct answer but we don't understand why.

Hi knelson and friend! :smile:

Newton's second law :

force = rate of change of momentum​

so if you multiply that by time, you get:

force x time = change of momentum :smile:
 
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