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Question

A body of mass m is moving with a uniform speed v along a circle of radius r, what is the average acceleration in going from A to B?

  1. 2 v to the power of 2 end exponent divided by pi r    
  2. 2 square root of 2 v to the power of 2 end exponent divided by pi r    
  3. v to the power of 2 end exponent divided by pi r    
  4. None of these    

The correct answer is: 2 square root of 2 v to the power of 2 end exponent divided by pi r


    Here, T equals fraction numerator 2 pi r over denominator 4 v end fraction equals fraction numerator pi r over denominator 2 v end fraction
    Change in velocity is going from A to B = v square root of 2
    Average acceleration equals fraction numerator v square root of 2 over denominator pi r divided by 2 v end fraction equals fraction numerator 2 square root of 2 v to the power of 2 end exponent over denominator pi r end fraction

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