Question

PHYSICS

A cable of resistance 10Ω carries electric power from a generator producing 250kW at 10,000V. The current in the cable is

(A)1000A

(B)250A

(C)100A

(D)25A


The answer is (D)

I want to ask why can't I use P=I^2R formula?
the answer is only coming correct by P=VI​

Answer 1

Answer:

R= 10=12 ohm

P=250kW = 250000w

V=1000v

I=p/v = 250000/10000=25A

P=I^2 R= 25×25×12 = 7500 w =7.5kW

V=IR = 25 × 12 = 300 V