Question

please tell me the answer of example 1.12 of ncert physics class 12​

Answer 1

Answer:

Refer to the arrangement of charges in Fig. 1.6 and a Gaussian surface of radius R with Q at the centre. Then

(a) total flux through the surface of the sphere is ‒Q/εo

(b) field on the surface of the sphere is ‒Q/(4πεoR2)

(c) flux through the surface of sphere due to 5Q is zero

(d) field on the surface of sphere due to –2Q is same everywhere

Solution 1.12: (a, c)

Gauss' law states that total electric flux of an enclosed surface is given by q/εo. Here, q is the net charge enclosed by the Gaussian surface.

From the figure,

Net charge inside the surface is = Q ‒ 2Q = ‒ Q.

Net flux through the surface of the sphere = ‒ Q/εo

Explanation: