Q.

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: The potential (V) at any axial point, at 2 m distance (r) from the centre of the dipole of dipole moment vector P of magnitude, 4×10-6C m, is ±9×103 V.

Reason R: V=±2P4π0r2, where r is the distance of any axial point, situated at 2 m from the centre of the dipole.

In the light of the above statements, choose the correct answer from the options given below.                [2024]

1 Both A and R are true and R is the correct explanation of A.  
2 Both A and R are true and R is NOT the correct explanation of A.  
3 A is true but R is false.  
4 A is false but R is true.  

Ans.

(3)

Potential at any axial point of a dipole is

V=±|p|4πε0r2

   V=±4×10-6×9×109(2)2=±9×103V

So, assertion is true but reason is false.