If radius of  nucleus is estimated to be 3.6 Fermi then the radius nucleus

• 6 fermi

• 8 fermi

• 4 fermi

• 4 fermi

A nuclear transformation is denoted by X(n, α) . Which of the following is the nucleus of element X?

Two spherical conductor B and C having equal radii and carrying equal charges in them repel each other with a force F when kept apart at some distance. A third spherical conductor having same radius as that of B but uncharged brought in contact with B, then brought in contact with C and finally removed away from both. The new force of repulsion, between B and C is

• F/4

• 3F/4

• 3F/8

• 3F/8

A nucleus disintegrates into two nuclear parts which have their velocities in the ratio 2:1. The ratio of their nuclear sizes will be

• 2^1/3:1

• 1:3^1/2

• 3^1/2:1

• 3^1/2:1

The binding energy per nucleon of deuteron (²₁H) and helium nucleus (⁴₂He) is 1.1 MeV and 7 MeV respectively. If two deuteron nuclei react to form a single helium nucleus, then the energy released is

• 13.9 MeV

• 26.9 MeV

• 23.6 MeV

• 23.6 MeV

26.

An α-particle of energy 5 MeV is scattered through 180° by a fixed uranium nucleus. The distance of the closest approach is of the order of

• 1 Å

• 10⁻¹⁰ cm

• 10⁻¹² cm

• 10⁻¹² cm

Which of the following particle when bombards on ⁶⁵Cu will turn into ⁶⁶Cu ?

• Proton

• Neutron

• Electron

• Alpha particle

8 g of Cu⁶⁶ undergoes radioactive decay and after 15 minutes only 1 g remains. The half-life, in minutes, is then

• 15 ln (2) / ln(8)

• 15 ln (8) / ln (2)

• 15/8

• 8/15

For a light nuclei, which of the following relation between the atomic number (Z) and mass number (A) is valid ?

• A = Z/2

• Z = A

• Z = A/2

• Z = A²

During β⁻ emission,

• a neutron in the nucleus decays emitting an electron

• an atomic electron is ejected

• an electron already present within the nucleus is ejected

• a part of the binding energy of the nucleus is converted into an electron