Question

The radius of a spherical nucleus as measured by electron scattering is $3.6$ fm. What is the mass number of the nucleus most likely to be?

• A. 27
• B. 40
• C. 56
• D. 120

Answer 1

Answer: (A)

27

Answer 2

: Nuclear radius, $R = R_{0}(A)^{1/3}$

Where A is the mass number of a nucleus

Given, $R = 3.6fm$

$\therefore 3.6fm = (1.2fm)(A^{1/3})\lbrack\because R_{0} = 1.2fm\rbrack$

Or $A = (3)^{3} = 27$