A hot electric iron has a resistance of $80\,\Omega $ and is used on a $200\, V$ source. The electrical energy spent, if it is used for two hours, will be ........... $Wh$
Medium
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(c) Energy $\frac{{{V^2}}}{R}t = \frac{{200 \times 200 \times 2}}{{80}} = 1000\,Wh$
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