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3 years ago

title="\huge\sf\underline\blue{⚓☠Question ☠}" alt="\huge\sf\underline\blue{⚓☠Question ☠}" align="absmiddle" class="latex-formula">
An electric iron consumes energy at a rate of 840 W when heating is at the maximum rate and 360 W when the heating is at the minimum. The voltage is 220 V. What are the current and the resistance in each case?

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Physics

1 answer:

Aloiza [94]3 years ago

8 0

Answer:

See Explanation

Explanation:

We know that;

P= IV

Where;

P = power

I= current

V = voltage

Here, we have a voltage of 220V

Hence, for maximum rate;

P= IV

I = P/V

P = 840 W

V= 220 V

I= 840 W/220 V

I= 3.8 A

V = IR

R = V/I

R = 220/3.8

R = 57.9 Ω

For minimum heating;

P= 360 W

V= 220 V

I = P/V

I = 360 W/220V

I= 1.6 A

V= IR

R = V/I

R = 220 V/1.6 A

R = 137.5 Ω

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