JEE Main201912 Jan 2019Evening ShiftPhysicsKinetic Theory of GasesActual
An ideal gas is enclosed in a cylinder at pressure of 2 atm and temperature, 300 K . The mean time between two successive collisions is 6 × 10 - 8 s . If the pressure is doubled and temperature is increased to 500 K , the mean time between two successive collisions will be close to:
Options
- A2 x 10 - 7 s
- B3 x 10 - 6 s
- C0 . 5 x 10 - 8 s
- D4 x 10 - 8 s
Correct answer
D. 4 x 10 - 8 s
Step-by-step solution
τ = 1 2 n π d 2 v a v g Where n = number of molecules per unit volume. τ ∝ V T ⇒ τ ∝ T P τ 2 τ 1 = T 2 T 1 . P 1 P 2 ⇒ τ 2 = 6 × 10 - 8 × 5000 300 × 2 4 ≈ 4 × 10 - 8 s