Question

an electric iron consume energy ata a rate of 840w when heating is at the maximum rate and 360w when the heating id at the minimum. the voltage is 220v. what are the current and the resistance in each case ?​

Answer 1

★ Refer to attachment...

Answer 2

Answers

When heating at max rate,

power, P = 840W

V = 220V

We know P = VI

⇒ 840 = 220 × I

⇒ I = 840/220

⇒ I = 4 A

R = V/I = 220/4 = 55 Ω

So current = 4A and resistance = 55Ω

When heating at minimum rate,

power, P = 360W

V = 220V

We know P = VI

⇒ 360 = 220 × I

⇒ I = 360/220

⇒ I = 1.636 A

R = V/I = 220/1.636 = 134.45 Ω

So current = 1.636A and resistance = 134.45Ω