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An electric iron consumes energy at the ...

An electric iron consumes energy at the rate of 420 W when heating is at the maximum rate and 180 W when heating is at the minimum rate. The applied voltage is 220V. What is the current in each case.

Text Solution

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Given: In the first case
The power consumed by an electric iron P = 240V
Applied voltage
i.e., potential difference , V = 220V
To find: Current, I = ? (in each case)
P = VI `implies therefore I = (P)/(V) = (420)/(220) = (21)/(11)`
When heating at maximum rate, `I = (21)/(11)` ampere
(or) I= 1,909 A
Heating at minimum rate, the rate at which energy is consumed , P = 180 W
Applied voltage, V = 220V
`I=(P)/(V) implies I = (180)/(220)`
`= (9)/(11)A` (or) I = 0.818 A
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