NEST (National Entrance Screening Test) Physics: Questions 1 of 58
» Physics and Measurement » Dimensional Analysis and Its Applications
Appeared in Year: 2007
MCQ▾
Question
The scattering of an electromagnetic wave by a charged particle of charge and mass is described in terms of the ‘Thomson Cross Section’ , which has the dimension of area. On the basis of dimensional analysis, the possible formula for is – [The symbols have the usual meanings. ]
Choices
Choice (4)  Response  

a. 


b. 


c. 


d. 


Answer
a.
Explanation

Since, the dimension of ‘Thomson Cross Section’ is same as dimension of area.

For other physical quantities, dimensions are given as,

For,

Dimension of R. H. S. are,
Therefore choice, is correct.