A sample of an ideal gas is in a tank of constant volume. The sample absorbs heat energy so that its temperature changes from 387 K to 774 K. If v1 is the average speed of the gas molecules before the absorption of heat and v2 their average speed after the absorption of heat, what is the ratio v2 v1 ? 1. v2 v1 = √ 2 2. v2 v1 = 2 3. v2 v1 = 1 2 4. v2 v1 = 4 5. v2 v1 = 1

Ratio v₂/v₁ = √2

Explanation:

We are given that ;

Initial temperature (T1) = 387K

Final temperature (T2) = 774K

Now, according to kinetic theory of gases, the average speed is proportional to the square root of the absolute temperature. The speed is given by:

v = √( 3∙R∙T/M)

Where;

R = universal gas constant,

T = absolute temperature,

M = molar mass of the gas molecules

Thus, v₁ = √(3∙R∙T₁/M)

Since it's same gas,

v₂ = √( 3∙R∙T₂/M)

Hence,

Ratio v₂/v₁ = √( 3∙R∙T₂/M)/√( 3∙R∙T₁/M) = √(T₂/T₁) = √(774K/387K) = √2

gravitational energy

electrical energy

kinetic energy

ligh energy