• question_answer A block of mass M is pulled along a horizontal frictionless surface by a rope of mass m. If a force P is applied at the free end of the rope, the force exerted by the rope on the block is [AIEEE 2003] A) $\frac{P\,m}{M+m}$ B) $\frac{P\,m}{M-m}$ C)             P D) $\frac{P\,M}{M+m}$

 [d] Let acceleration of system (rope + block) is a along the direction of applied force. Then, $a=\frac{P}{M+m}$                .. (i) Frictionless surface Draw the FBD of block and rope as shown in figure below. where, T is the required parameter (i.e., force) For block       T = Ma $\Rightarrow$   $T=\frac{MP}{M+m}$ [from Eq. (i)]