Does Equal Force Result in Equal Momentum for Different Masses?

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The discussion centers on the relationship between force, mass, and momentum, specifically addressing whether equal forces applied to bodies of different masses result in equal momentum. It is established that while the impulse (change in momentum) is equal for both bodies, the momentum after the application of force will differ due to the mass difference. Additionally, the calculation of impulse for a 0.2kg rubber ball dropped from a height, striking the ground at 30m/s and rebounding at 20m/s, confirms that the impulse is 10 upward, calculated as 0.2 * 20 - 0.2 * (-30).

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blackout85
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Please check over my work

Two bodies of unequal mass, placed at rest on a frictionless surface, are acted on by an equal horizontal forces for equal times. Just after the forces are removed, the body of greater mass will have:
The body of greater mass will have the the greater speed, the greater acceleration, the smaller momentum, the greater momentum, or the same amount as the other body.

Would the answer be the larger body would have the same amount amount of momentum as the other body because P(before)=P(after). The momentum would have to come out the same in order for that to be right.

second question:

A 0.2kg rubber ball is dropped from the window of a building. It strikes the sidewalk below at 30m/s and rebounds up at 20m/s. The impulse during the collision would be:

my work:
0.2 (-30m/s) - 0.2 (20m/s) = 10 upward

Please let me know if I am on the right track and let me know where I might have gone wrong:redface:
 
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blackout85 said:
Would the answer be the larger body would have the same amount amount of momentum as the other body because P(before)=P(after). The momentum would have to come out the same in order for that to be right.

Yes, but you should use the fact that the impulse of the force equals the change of momentum, and since the impulse is equal for both bodies, you have F*t = m1v1 = m2v2.

blackout85 said:
A 0.2kg rubber ball is dropped from the window of a building. It strikes the sidewalk below at 30m/s and rebounds up at 20m/s. The impulse during the collision would be:

my work:
0.2 (-30m/s) - 0.2 (20m/s) = 10 upward

Please let me know if I am on the right track and let me know where I might have gone wrong:redface:

Looks good.

Edit: the change in momentum (i.e. the impulse) should actually be: [tex]0.2\cdot 20\vec{j}-0.2\cdot(-30)\vec{j}=10\vec{j}[/tex], which means 10 upwards.
 
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