When an electric iron is connected to $230 V$ mains, $750 W$ power is consumed. $(i)$ What is the resistance of its heating element? $(i i)$ What current is passed through it?

Open in App

Solution

Working voltage, $V = 230 V$
Power consumed, $P = 750 W$
$(i)$ Let $R$ be the resistance of the heating element
$P = \frac{V^{2}}{R}$ or $R = \frac{V^{2}}{P}$
$R = \frac{230 \times 230}{750} = 70.53 Ω$
$(i i)$ Current through the iron, $I = \frac{P}{V} = \frac{750}{230} = 3.26 A$
Therefore, the current that is passed through the iron is $3.26 A$ .
Resistance of the heating element of the iron is $70.55 Ω$ .

Suggest Corrections

Similar questions

Q. An electric iron is connected to the mains power supply of 220 V. When the electric iron is adjusted at 'minimum heating' it consumes a power of 360 W but at 'maximum heating' it takes a power of 840 W. Calculate the current and resistance in each case.

An electrical appliance has a resistance of $25 Ω$ when this electrical appliance is connected to a 230 V supply line, the current passing through it will be:

Q. An electric bulb is rated

^{'} 250 W, 230 V^{'}

. Calculate:
(i) the energy consumed in one hour, and
(i) the time in which the bulb will consume

1.0 k W h

energy when connected to

230 V

mains.

Q. An electric iron draws a current of

4 A

when connected to a

220 V

mains. Its resistance must be:

Q. An electrical appliance has a resistance of 25 Ω. When this electrical appliance is connected to a 230 V supply line, the current passing through it will be:

(a) 0.92 A
(b) 2.9 A
(c) 9.2 A
(d) 92 A

Join BYJU'S Learning Program

When an electric iron is connected to 230V mains, 750W power is consumed. (i) What is the resistance of its heating element? (ii) What current is passed through it?

Working voltage, V=230VPower consumed, P=750W(i) Let R be the resistance of the heating elementP=V2R or R=V2PR=230×230750=70.53Ω(ii) Current through the iron, I=PV=750230=3.26ATherefore, the current that is passed through the iron is 3.26A.Resistance of the heating element of the iron is 70.55Ω.

When an electric iron is connected to $230 V$ mains, $750 W$ power is consumed. $(i)$ What is the resistance of its heating element? $(i i)$ What current is passed through it?