Question

Imagine a short dipole is at the centre of a spherical surface. If magnitude of electric field at a certain point on the surface of sphere is 10 N/C, then which of the following cannot be the magnitude of electric field anywhere on the surface of sphere

(A) 4 N/C 

(B) 8 N/C 

(C) 16 N/C 

(D) 20 N/C 

(E) 15 N/C

Answer 1

Correct option (A) 4 N/C

Explanation:

If E_axial = 10 N/C 

then E_eq = 5 N/C

If E_eq = 10 N/C

then E_axial = 20 N/C

So magnitude of electric field at any point 

5N/C≤ E≤ 20 N/C