Energy and Power - Engineering

Q1:

When the current through a 12 k resistor is 8 mA, the power is

A 7.68 mW

B 768 mW

C 7.68 W

D 76.8 W

ANS:B - 768 mW

W = I^2R.
W = 8^2 * 12000,
W = 768000/1000,
W = 768mW.