Question

Find the vector potential when the field intensity 60x^2 varies from (0,0,0) to (1,0,0).

(a) 120

(b) -20

(c) -180

(d) 60

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The above asked question is from Magnetic Vector Potential in division Magnetostics of Electromagnetic Theory

Answer 1

Right answer is (b) -20

The explanation is: The field intensity H = -Grad(V). To get V, integrate H with respect to the variable. Thus V = -∫H.dl = -∫60x^2 dx = -20x^3 as x = 0->1 to get -20.