Calculate Change in Momentum of 65kg Runner After Half Revolution

Thread starter Masafi
Start date Jan 17, 2010
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Change Change in momentum Momentum

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A 65kg runner moving at 5m/s around a circular track experiences a change in momentum after half a revolution. The initial momentum is +325Ns, and after half a revolution, it becomes -325Ns. This results in a total change in momentum of 650Ns. However, the accepted answer in the discussion is 625Ns, indicating a potential discrepancy in calculations. The key point is that the change in momentum is significant due to the direction change of the runner.

Jan 17, 2010

Masafi

A runner of mass 65kg is running around a circular track at 5m/s. What is the magnitude of the change in his momentum from start to end after half a revolution?

My answer if 650Ns, but the answer is written as 625Ns.

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Jan 17, 2010

Stonebridge

I would say you are correct.
The momentum changes from +325Ns to -325Ns

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