Question

Find the magnetic flux density of the material with magnetic vector potential A = y i + z j + x k.

(a) i + j + k

(b) –i – j – k

(c) –i-j

(d) –i-k

This question was posed to me by my school principal while I was bunking the class.

Asked question is from Magnetic Field Density in portion Magnetostics of Electromagnetic Theory

Answer 1

Right option is (b) –i – j – k

For explanation I would say: The magnetic flux density is the curl of the magnetic vector potential. B = Curl(A). Thus Curl(A) = i(-1) – j(1) + k(-1) = -i – j – k. We get B = -i – j – k.