Question

$10000$ small balls each weighing $1$ g strike one square cm of area per second with a velocity $100$ in a normal direction and rebound with the same velocity

Answer 1

$Noofballs=10000$

$massofeachball=1g$

$area=1c{m}^2={10}^{-4}{m}^2$

$Pressure=\frac{10000\times {10}^{-3}\times (v–(–v\left)\right)}{{10}^{-}4}$

= as ball rebound with same velocity hence $v2=–v$

$=\frac{10000\times {10}^{-3}\times 2\times 100}{{10}^{-4}}$

$=2\times {10}^{7}N/m^2$