Question

Nuclear radius depends on the mass number of the element.

1. Write down the expression for nuclear radius.

2. Prove that the density of the nucleus is independent of mass number A.

3. Read the following statement and choose the correct option.

“Electric dipole moment is zero for nuclei in stationary state.”

Assertion: 

All nuclei have spherical symmetry about the centre of mass.

Reason: 

The zero dipole moment for stationary nuclei is due to the symmetry about the centre of mass.

• Assertion and reason are true. 
• Assertion is false reason is true 
• Assertion is true reason is false 
• Assertion and reason are false.

Answer 1

1. R = R₀A^1/3

2. Density of nucleus = (mass of the nucleus)/(volume of the nucleus)

This shows that nuclear density is independent of mass number. 

3. (ii) Assertion is false reason is true.