Highly energetic electrons are bombarded on a target of an element containing `30` neutrons. The ratio of radii of nucleus to that of Helium nucleus is `141//3`. The atomic number of nucleus will be.

Options

A. 25
B. 26
C. 56
D. 30

Answer

B

Explanation

As `R=R_(0)A^(1//3)rArr(R_(1))/(R_(2))=(A_(1)/(A_(2)))^(1//3)rArr(R)/(R_(He))=((A)/(4))^(1//3)`
`rArr (14)^(1//3)=((A)/(4))^(1//3)rArr A=56 (or) Z=A-N`
`Z= 56-30= 26`