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If reaction is R and coefficient of friction isblank mu, what is work done against friction in moving a body by distance d?

Physics-General

  1. 2 mu R d    
  2. fraction numerator mu R d over denominator 4 end fraction    
  3. mu R d    
  4. fraction numerator mu R d over denominator 2 end fraction    

    Answer:The correct answer is: mu R d
    As shown a block of mass M blankis lying over rough horizontal surface. Letblank mu be the coeeficient of kinetic friction between the two surfaces in contact. The force Of friction between the block and horizontal surface is given by
    F equals mu R equals mu M g (because R equals M g right parenthesis
    To move the block without acceleration, the force (P)required will be just equal to the force of friction , ie ,
    P equals F equals mu R
    If d is the distance moved , then work done is given by
    W equals P cross times d equals mu R d

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