How High Does a Swing Reach After Pumping Stops?

AI Thread Summary
The discussion centers on a physics problem involving a child on a swing who reaches a speed of 6.7 m/s before stopping her pumping. The key concepts include the conservation of energy, where potential energy (PE) and kinetic energy (KE) are balanced. The participant initially expresses confusion about the parameters needed to solve the problem, specifically regarding the velocity's designation and the absence of mass and height values. Ultimately, the participant resolves the issue independently. The conversation highlights the importance of understanding energy conservation in solving motion-related problems.
Snape1830
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A child on a swing pumps hard and achieves a speed of 6.7 m/s at the swing’s lowest point. She then stops pumping. How high above the lowest point does the swing reach after that?

I honestly have no idea how to go about solving this. I know the velocity is 6.7 m/s (but is it final or initial or both?). I also know gravity is 9.8 m/s. But I don't know anything else?

I know the equation for conservation of energy is PEf+KEf = PEi+KEi. I know PE= mgh and KE= .5mv2 However, I have no idea how to do this because I don't have the height or the mass, and I don't know if 6.7 m/s is the initial, final, or both. I'm just completely lost.

Please help! Thanks!
 
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