JEE Main & Advanced Physics NLM, Friction, Circular Motion Sample Paper Topic Test - Friction

  • question_answer
    A block A is kept on a block B. Friction between B and ground is negligible. \[{{\mu }_{s}}\] and \[{{\mu }_{K}}\] are the coefficients of static and kinetic friction between A and B, respectively. A horizontal force F is applied on A. \[{{a}_{1}}\] is the acceleration of B just before A slips on B and \[{{a}_{2}}\] is the acceleration of B after A slips on B. Assume \[{{\mu }_{s}}>{{\mu }_{K}}\]. Then

    A) \[{{a}_{1}}>{{a}_{2}}\]         

    B) \[{{a}_{1}}<{{a}_{2}}\]

    C) \[{{a}_{1}}={{a}_{2}}\]                     

    D) None of these

    Correct Answer: A

    Solution :

    Just before slipping occurs force acting on B is,  \[{{\mu }_{s}}mg\], where m is the mass of block A. After the slipping the force on block B is \[{{\mu }_{K}}mg\]. Force before slipping is more, so acceleration before slipping should be more.

You need to login to perform this action.
You will be redirected in 3 sec spinner