Q 11-04-020JEE MainAIEEE 2007Easy
Two blocks of masses $m$ and $M$ are placed on a horizontal frictionless table and connected by a light spring. Mass $M$ is pulled to the right with a force $F$. If the acceleration of mass $m$ is $a$, then the acceleration of mass $M$ will be
Answer: (A) $\dfrac{F - ma}{M}$
Concept. The spring force is the only horizontal force on $m$, so it equals $ma$.
Step 1. Block $M$. $F - ma = Ma'$.
Step 2. Solve. $a' = \dfrac{F - ma}{M}$.
Answer. $\dfrac{F - ma}{M}$ (Option A).
Solution by Sreeraj P, M.Sc Physics
