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
A chain of mass $\mathrm{M}$ is placed on a smooth table with $1 / \mathrm{n}$ of its length $\mathrm{L}$ hanging over the edge. The work done in pulling the hanging portion of the chain back to the surface of the table is
PhysicsWork Power EnergyBITSATBITSAT 2009
Options:
  • A $\mathrm{MgL} / \mathrm{n}$
  • B $\mathrm{MgL} / 2 \mathrm{n}$
  • C $\mathrm{MgL} / \mathrm{n}^{2}$
  • D $\mathrm{MgL} / 2 \mathrm{n}^{2}$
Solution:
2128 Upvotes Verified Answer
The correct answer is: $\mathrm{MgL} / 2 \mathrm{n}^{2}$
$\quad \mathrm{W}=$ change in $\mathrm{PE}$ of $\mathrm{COM}$ of hanging part
$$
=\frac{\mathrm{M}}{\mathrm{n}} \mathrm{g} \frac{\mathrm{L}}{2 \mathrm{n}}=\frac{\mathrm{MgL}}{2 \mathrm{n}^{2}}
$$

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.