Question

10,000 small balls, each weighing 1 g, strike one square cm of area per second with a velocity 100 m/s in a normal
direction and rebound with the same velocity. The value of pressure on the surface will be:
(a) 2 x 10^3 N/m2
(b) 2 x 10^5N/m2
(c) 10^7 N/m2
(d) 2 x10^7 N/m2

Answer 1

★★Question:-

✓✓10,000 small balls, each weighing 1 g, strike one square cm of area per second with a velocity 100 m/s in a normal direction and rebound with the same velocity. The value of pressure on the surface will be:

• $(a)\:2×{10}^{3}N/{m}^{2}$

• $(b)\:2×{10}^{5}N/{m}^{2}$

• $(c)\:{10}^{7}N/{m}^{2}$

• $(d)\:2×{10}^{7}N/{m}^{2}$✔️

★★Answer:-

• $(d)\:2×{10}^{7}N/{m}^{2}$

★★Explanation:-

$P=\dfrac{F}{A}$

$=\dfrac{n\:mv-mv}{A}$

$=\dfrac{2mnv}{A}$

$=\dfrac{2×10^{-3}×10^4×10^2}{10-^4}$

$\huge\boxed{\boxed{{=2×10^7N/m^2}}}$