F=2mnVcosθ⇒P=A2mnVcosθ
⇒P=2×2×10−42×3.32×10−27×1023×103
⇒P=2.35×103Nm−2
JEE Main 2018 — Physics Mechanics
The mass of a hydrogen molecule is 3.32×10−27kg. If 1023 hydrogen molecules strike, per second, a fixed wall of the area 2cm2 at an angle of 45o to the normal, and rebound elastically with a speed of 103ms−1, then the pressure on the wall is nearly:
Held on 8 Apr 2018 · Verified 6 Jul 2026.
4.70×102Nm−2
2.35×103Nm−2
4.70×103Nm−2
2.35×102Nm−2
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