i have a tetherball that goes from a radius of 1 m to a radius of 2 m.(adsbygoogle = window.adsbygoogle || []).push({});

the initial speed is 1 m/s, whats the final speed?

if its 0.5 m/s the energy of the ball halfs so it must be transferred to earth via pole thickness so the earth gains kinetic energy so gains momentum,so the momentum of the whole system grows

if its 1 m/s then conservation of momentum fails because momentum has doubled and besides some torque has been applied to earth via the pole thickness

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# Homework Help: Still stuck in momentum vs energy on a tetherball

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