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MHT CET20225 Aug 2022Morning ShiftPhysicsCenter of Mass, Momentum and CollisionActual

A wall is hit elastically and normally by ' n ' balls per second. All the balls have the same mass ' m ' and are moving with the same velocity ' u '. The force exerted by the balls on the wall is

Options

  1. A2 mnu ^2
  2. B2 mnu
  3. C1 2 mnu ^2
  4. Dmnu

Correct answer

B. 2 mnu

Step-by-step solution

The correct option is (B). Force is related to momentum change by following relation, F = dp dt Momentum change per second, dp dt = n ( mu -(- mu ))=2 nmu Therefore, F =2 nmu

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