Question

A)Define electrical power. An electrical device of resistance is connected to a source of voltage V and pulls a current l . Generate an expression for power in terms of current and resistance,

B)two electric bulbs are rated at 100W, 220V and 60W; 220V are connected in parallel to an electric ray 220 V Find the current pulled by the bulbs from the main.​

Answer 1

electric power: the rate of electrical work done per unit time

we knew

P= V*I---(1)

by ohms law

V = IR

substuting in (1)

= I^2/R

B) P = V *I

100/220 = I

0.45 A

60/220 = I'

0.27 A

total current = 0.27 + 0.45= 0.72A