Question

According to the kinetic theory of gases, the pressure exerted by a gas on the walls is measured as

• A. rate of change of momentum imparted to the walls per second per unit area
• B. momentum imparted to the walls per unit area
• C. change of momentum imparted to the walls per unit area.
• D. change in momentum per unit volume

Answer 1

Answer: (A)

According to Newton's second law:
Force $=$ rate of change of momentum
$F=\frac{dp}{dt}$
Particles impart momentum on the wall.
And the rate of change of momentum is the force exerted on the wall.
Pressure is force per unit area.
Hence pressure exerted by gas on the wall is the rate of change of momentum imparted to the walls per second per unit area.