If the number of radius of ²⁷Al is 3.6 Fermi, the approximate nuclear radius of ⁶⁴Cu in Fermi is:

Options

(a) 2.4
(b) 1.2
(c) 4.8
(d) 3.6

Correct Answer:

4.8

Explanation:

The radius of the nuclears is directly proportional to cube root of atomic number i.e., R ∞ A¹/³
R = R₀A¹/³, where R₀ is a constant of proportionality
R₂ / R₁ = (A₂ / A₁)¹/³ (64 / 27)¹/³ = 4/3
where R₁ = radius of ²⁷Al, and A₁ = Atomic mass number of Al
R₂ = the radius of ⁶⁴Cu and A₂ = Atomic mass number of C4.
R₂ = 3.6 x 4/3 = 4.8 m.