Question

Find the potential of the function V = 60cos θ/r at the point P(3, 60, 25).

(a) 20

(b) 10

(c) 30

(d) 60

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This interesting question is from Relation of E,D,V in section Electrostatic Fields of Electromagnetic Theory

Answer 1

Correct choice is (b) 10

Explanation: Given V = 60cos θ/r. For r = 3m and θ = 60, we get V = 60cos 60/3 = 20cos 60 = 10 units.