Question

Calculate the total energy stored in the inductor if the current value is 4 A and inductance values are 1 H and 2 H.

(a) 72 J

(b) 22 J

(c) 82 J

(d) 24 J

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This interesting question is from Electric Motors in section Braking of Electric Motors of Electric Drives

Answer 1

Right option is (d) 24 J

Easiest explanation: The energy stored in the inductor is .5×Leq×I^2. The value of Leq=1+2=3 H. The total amount of energy stored in the inductor in the steady state condition. E=.5×eq×I^2=.5×3×4×4=24 J.