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electric iron consumes energy at a rate of 840 W when heating iaAnat the maximum rate and 360 W when the heating is at the minimumThe voltage is 220 V. What are the current and the resistance in eachase

Answer» <p>At maximum heating, power is P = 840 W</p><p>We know, P = V^2/R</p><p>=&gt; R = V^2/P</p><p>Working voltage is 220 V</p><p>So, resistance at maximum heating is = 220^2/840 = 57.6 Ω</p><p>The current is found as, I = P/V (since, P = VI)</p><p>So, current at maximum heating is = 840/220 = 3.8 A</p><p>At minimum heating, power is = 360 W</p><p>The resistance at minimum heating will be = 220^2/360 = 134.4 Ω</p><p>The current at minimum heating will be = 360/220 = 1.6 A</p>


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