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):
[Main Online April 11, 2015]
(a) 2(L−nr)mv2
(b) L−2nrmv2
(c) L−nrmv2
(d) zero