Question

When is the magnetic flux said to be negative?

(a) θ = 180^o

(b) θ = 360^o

(c) θ = 90^o

(d) θ = 0^o

This question was addressed to me in an internship interview.

This intriguing question originated from Electromagnetic Induction in portion Electromagnetic Induction of Physics – Class 12

Answer 1

Right option is (a) θ = 180^o

Explanation: If the normal points in the opposite direction of the field, then θ = 180^o and the flux is taken as negative. If the magnetic field is pointing opposite the direction of the surface area then the value of this flux is negative.