Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
In a system of two particles of masses 'mi' and 'm2', the first particle is moved by a distance 'd' towards the centre of mass. To keep the centre of mass unchanged,
the second particle will have to be moved by a distance
PhysicsCenter of Mass Momentum and CollisionMHT CETMHT CET 2020 (19 Oct Shift 2)
Options:
  • A $\frac{\mathrm{m}_{1}}{\mathrm{~m}_{2}} \mathrm{~d}$, towards the centre of mass.
  • B $\frac{\mathrm{m}_{2}}{\mathrm{~m}_{1}} \mathrm{~d}$, away from the centre of mass.
  • C $\frac{\mathrm{m}_{2}}{\mathrm{~m}_{1}} \mathrm{~d}$, towards the centre of mass.
  • D $\frac{\mathrm{m}_{1}}{\mathrm{~m}_{2}} \mathrm{~d}$, away from the centre of mass.
Solution:
2098 Upvotes Verified Answer
The correct answer is: $\frac{\mathrm{m}_{1}}{\mathrm{~m}_{2}} \mathrm{~d}$, towards the centre of mass.
the 2 masses are miand m2
let $x$ and $y$ be the distance of miand $m 2$ from the centre of mass respectively...
now, $m_{1} x=m_{2} y$
the mass $m 1$ is moved by a distance $d$,
let the mass $\mathrm{m} 2$ be moved by a distance $\mathrm{D}$
therefore, $m_{1}(x-d)=m_{2}(y-D)$
$\mathrm{m}_{1} \mathrm{x}-\mathrm{m}_{1} \mathrm{~d}=\mathrm{m}_{2} \mathrm{y}-\mathrm{m}_{2} \mathrm{D}$
by eqn (i) $m_{1} x=m_{2} y$
$=>-\mathrm{m}_{1} \mathrm{~d}=-\mathrm{m}_{2} \mathrm{D}$
$=\mathrm{D}=\frac{\mathrm{m}_{1} \mathrm{~d}}{\mathrm{~m} 2}$

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.