Rolls down a ramp and bounces back up

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A user seeks help with a physics homework problem involving a 500 g cart rolling down a frictionless ramp and bouncing off a rubber block. They calculated the net force, velocity at the bottom, and time to reach the bottom but struggled with the rebound distance. Another user shared their approach using the area under the force curve to find momentum and velocity after the collision, but expressed confusion over the resulting speed. Several participants discussed their methods for calculating the final velocity and questioned the initial velocity value. The conversation highlights common challenges in applying conservation of momentum and energy principles in physics problems.
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Hi guys (and girls), I'm kinda new to these forums. What I mean by that is I haven't yet posted anything, but I have been lurking around for a few weeks. Anyways, I'm stuck on this homework problem.


A 500 g cart is released from rest 1.0 m from the bottom of a frictionless, 30 degree ramp. The cart rolls down the ramp and bounces off a rubber block at the bottom. The figure shows the force during the collision.

knight_Figure_09_30.jpg



I have setup my force diagram and found the following information:

Fnet(x): 2.45N
Velocity at bottom of ramp: 3.13m/s
Time to reach bottom of ramp: 0.64s



Unfortunately, I don't know what to do next.

This problem is very elementary I know, but all help will be appreciated.
 
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So...what is it asking you to do?
 
Sorry guys. I forgot to ask the question...haha. But anyways, I figured it out. I forgot an important part of the conservation of momentum theorem.

Just for the record, the question was "How far up the ramp does the cart rebound?"
 
Hey guys, I have the same problem and I just happened to find this thread

I took J which is the area under the force curve in the diagram so I have 26.7N

Then P2x = p1x + Jx = (3.13m/s * 0.500kg) + 26.7N = 28.265 kgm/s

Then V2x = 28.265kgm/s / 0.500kg = 56.53m/s? I think I might have screwed up because I don't think it can have that velocity.

Now I don't know where to go once I have the velocity

nevermind I didnt convert ms to s correctly, now I have a post collision velocity of 8.47m/s but I don't know what to do after
 
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Hi,

I have the same question but where's the 3.13m/s coming from?
Here I try to do it the fancy way.
I did
\[ v^2_f = v^2_i + 2ad \]<br /> \[ v^2_f = 0+ 2(mgsinx)(1)\]<br /> <br /> so /[v_f = 2.21 m/s \]

I took area like the last guy expcept I got 2.67Ns

Then I did whole bunch of other stuff to get wrong answer so can somebody help me with the first part?
 
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