A sphere rolls on a rough horizontal surface with a velocity v collides with a smooth vertical wall elastically. Find its velocity when its starts pure rolling backward.(adsbygoogle = window.adsbygoogle || []).push({});

I feel that since collision is elastic the enrgy must be conserved instantaneously. But however there is friction. However in how much time will the pure rolling start in backward direction is not clear. I don't understand how to start. Can anyone here please help?

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# Homework Help: Rolling of sphere - collision

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