 # Physics Practical Class 11 To study the variation in volume with pressure for a sample of air at constant temperature by plotting graphs between P and V, and between P and 1/V.Viva Questions with Answers

1) Only low-density gases obey Boyle’s and Charle’s law. Is it true or false?

a) True

b) False

Correct Option: (a)

Explanation: Since the ideal gas law is based on the assumptions of the kinetic theory of gases, Boyle’s and Charle’s laws are used to attain the ideal gas law. And the ideal gas law is only valid for low-density gases. Therefore, the above statement is true.

2) What is Boyle’s law?

At a constant temperature, the relation concerning the compression and expansion of a gas is known as Boyle’s law, which is also termed Mariotte’s law.

Physicist Robert Boyle articulated this empirical relation, which states that at a constant temperature, for a given quantity of gas, its pressure (p) is inversely proportional to its volume (v) and in equation form, it can be written as PV = k, a constant.

3) What does Charle’s law state?

Charles’s law states that if the pressure remains constant, then the absolute temperature of a fixed amount of gas is directly proportional to the volume occupied by it.

4) Give a daily life example of Boyle’s law.

One of the best daily life examples of Boyle’s law is a balloon. The balloon is magnified by blowing the air into it, and the balloon expands due to the pressure of the air pulling on the rubber. The pressure within the balloon rises when one end of the balloon is compressed, and hence it results in the outward expansion of the un-squeezed section of the balloon.

5) What is the average velocity of the molecules of an ideal gas?

The molecules possess all kinds of velocities in all possible directions, therefore, the average velocity of the molecules of an ideal gas is zero.

6) On what factor does the average kinetic energy of gas molecules depend?

The average kinetic energy of a gas is directly proportional to its absolute temperature, hence it only depends on the temperature.

7) What will be the degree of freedom of a triatomic gas?

Due to rotator motion, a triatomic gas molecule has 3 degrees of freedom, and due to translator motion, a triatomic gas molecule has 3 degrees of freedom.

8) For an ideal gas, what is the shape of a P-T curve?

For an ideal gas, the P-T curve is a straight line.

9) For an ideal gas, what is the shape of a V-T curve?

For an ideal gas, the V-T curve is a straight line.

10) What will be the compressibility factor for an ideal gas?

The compressibility of an ideal gas is always 1.