Nuclear Physics MSQ - Physics

Number of nuclei remaining after
n half lives is 

The correct answer is: 

= 1.09 × 10⁵ m/s

The correct answers are: The speed of the ion is 1.09 × 10⁵ m/s, The mass of the ion is 2.68 × 10^–26 kg

Mass No. = No. of p + No. of neutron

= 2.75 × 10²
A = 275
The correct answer is: 275

Mirror nuclei have same A but the number of neutrons & protons are reversed.
There is a slight difference in the masses of a proton & neutron. This apart from the different coulomb force in mirror nuclei result in the difference in their masses.

The correct answers are: Nuclei with same mass number but the number of neutrons and protons reversed are called mirror nuclei, The mirror nuclei have different masses, The difference in masses is due to the difference in the proton & neutron masses & difference in the coulomb energy.

mass remaining after 2000 years is

mass decayed = 0.58 mg

The correct answers are: 0.42 mg  material was left after 2000 years, 0.58 mg  material decayed in 2000 years

The correct answers are: Continuous βray spectrum instead of a discrete spectrum as would have been the case had there only been an electron emitted, Most electrons were emitted with energy much less than maximum kinetic energy., Non conservation of angular momentum, Non conservation of linear momentum

The correct answers are: spin dependent, charge independent, has repulsive core, same between two proton and two neutron

B.E./Neutron

Nuclei with smaller A fuse to form a nucleus of higher A which has more B.E./nucleon compared to the reactants. Nuclei with higher A(~200) fission into nuclei of smaller A which have higher B.E./nuclei  (thus they are more stable).

The correct answers are: Nuclei with lower mass number tend to undergo fusion, Nuclei with larger mass number tend to undergo nuclear fission

Deuteron emission 
α particle emission 
 has a lower mass number & from the B.E/nucleon v/s A plot, it can be concluded that  will have a greater B.E./nucleon as compared to 
∴  it would be more stable
∴  α decay is preferred

The correct answers are: ²³⁸Pu prefers to decay by emitting an α particle., Emitting an α particle results in a nucleus having greater binding energy per nucleon.

For an electron beam

~0.22 × 10¹⁰
= 2.2 × 10⁹ eV
= 2.2 GeV
For proton beams,

 

= 8.5 × 10⁶ eV

= 8.5 MeV

The correct answers are: The energy of a proton beam to probe the inside of a nucleus is of order MeV., The energy of an electron beam to probe the inside of a nucleus is of the order of GeV.