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If masses of all the molecules of a gas are halved and their speeds are doubled, then the ratio of initial and final pressures is

Options

  1. A1 : 2
  2. B2 : 1
  3. C4 : 1
  4. D1 : 4

Correct answer

A. 1 : 2

Step-by-step solution

Using the relation p = 1 3 mnv 2 V ...(i) and also p ′ = 1 3 m 2 n 2 v 2 V ...(ii) Dividing Eq.(ii) by Eq. (i), we get p ′ p = 2 So, p : p ′ = 1 : 2 The ratio of initial and final pressures is 1 : 2 .

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