**Question:**

**A large number $(n)$ of identical beads, each of mass $m$ and radius $r$ are strung on a thin smooth rigid horizontal rod of length $L(L>>r)$ and are at rest at random positions. The rod is mounted between two rigid supports (see figure). If one of the beads is now given a speed v, the average force experienced by each support after a long time is (assume all collisions are elastic):**

$\frac{\mathrm{mv}^{2}}{2(\mathrm{~L}-\mathrm{nr})}$

$\frac{m v^{2}}{L-2 n r}$

$\frac{\mathrm{mv}^{2}}{\mathrm{~L}-\mathrm{nr}}$

zero

Question of from chapter.

JEE Main Previous Year April 11, 2015

Correct Option: 2

**Solution:**

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