Board MCQ II PU PHYSICS (33) Chapter13: Nuclei and Radioactivity

Strongest force in nature is

• Electromagnetic force

• Weak nuclear force

• Strong nuclear force

• Gravitational force

Atomic number of a nucleus represents

• Number of protons

• Number of protons and neutrons

• Number of neutrons

• Number of nucleons

Mass number of a nucleus represents

• number of proton

• number of protons and electrons

• number of neutrons

• number of nucleons

Difference between mass number and atomic number of a nucleus represents

• Number of protons

• Number of protons and neutrons

• Number of neutrons

• Number of nucleons

If Z represents atomic number and A represents mass number of a nucleus, then charge of the nucleus is (e=magnitude of charge of electron)

• +Ae

• +(A-Z)e

• +(A+Z)e

• +Ze

Volume of a nucleus is directly proportional to

• Atomic number

• Atomic mass

• Radius of nucleus

• Density of nucleus

The nuclear force is

• attractive for distance r = 0.5 fm

• attractive for distance r < 0.8 fm

• repulsive for distarice > 0.8 fm

• repulsive for distance < 0.8 fm

If A is the mass number, radius of a nucleus is

• directly proportional to A^1/3

• directly proportional to A ³

• inversely proportional to A ^1/3

• inversely proportional to A ³

The value of energy band in insulators is __________ than 3 eV.

Radius of a nucleus of mass number A is given by (R_o is a constant)

• R = R_o A^1/3

• R = R_o A^1/2

• R = R_O + A^1/3

• R = R_O - A^1/3