Assertion (A) A charge q is placed on a height h/4 above the centre of a square of side b . The fluk associated with the square is independent of side length.
Reason (R ) Gauss 's law is independent of size of the Gaussian surface.

Options

A. both, Assertion and Reason are true and the Reason is correct explanation of the Assertion.
B. both, Assertion and Reason are true, but Reason is not the correct explanation of the Asserrtion.
C. Assertion is true, but the Reason is false.
D. both, Assertion and Reason are false.

Answer

a

Explanation

Here, both Assertion and Reasion are true and Reason is the correct explanation of the Assertion because electric flux linked with a gaussian surface is
`phi_(E) = oint_(S) = vec(E) . d Vec(s) = (1)/(in_(0))`
`xx` charge enclosed by the surface

If a charge `q` is placed at the centre `O` at the cube then electric flux through all the six faces of the cube is `= (q)/(in_(0))`
Electric flux through one face `= (1)/(6) (q)/(in_(0))`
which is independat of side length `b`.