The condition for maximum power in case of D.C. motor is

Q. The condition for maximum power in case of D.C. motor is

A.            back e.m.f. = 2 x supply voltage

B.            back e.m.f. = | x supply voltage

C.            supply voltage = | x back e.m.f.

D.            supply voltage = back e.m.f.

Answer: back e.m.f. = | x supply voltage