Estimate pressure of air molecules at 273 K, if mean square speed is 500m²/s² and density of air is 6kg/m³:
Correct answer: A. 1 x 10³ Pa
- A. 1 x 10³ Pa
- B. 2.5 x 10² Pa
- C. 1 x 10² Pa
- D. 2.7 x 10³ Pa
Explanation
Kinetic theory gives P = (1/3) x density x mean square speed. Substituting, P = (1/3) x 6 x 500 = 1000 Pa, which is 1 x 10^3 Pa.
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