Q.

A point charge causes an electric flux of 2×104 Nm2C1 to pass through a spherical Gaussian surface of 8.0 cm radius, centred on the charge. The value of the point charge is: (Given ε0=8.85×1012C2N1m2)          [2025]

1 17.7×108 C  
2 15.7×108 C  
3 17.7×108 C  
4 15.7×108 C  

Ans.

(1)

ϕ=2×104Nm2C

ϕ=qε0

 q=ε0ϕ=(8.85×1012)×(2×104)

q=17.7×108C