A molecule of mass ' $m$ ' moving with velocity ' $\mathrm{v}$ ' makes 5 elastic collisions with a wall of…
A molecule of mass ' $m$ ' moving with velocity ' $\mathrm{v}$ ' makes 5 elastic collisions with a wall of container per second. The change in momentum of the wall per second in 5 collisions will be
$10 \mathrm{mv}$
$5 \mathrm{mv}$
$\frac{1}{5} \mathrm{mv}$
$\frac{1}{10} \mathrm{mv}$
Solution
Change in momentum in each collision is $[\mathrm{mv}-(-\mathrm{mv})]=2 \mathrm{mv}$ Hence change in momentum in 5 collisions is $5 \times 2 \mathrm{mv}=10 \mathrm{mv}$