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प्रश्न
Which uses more energy : a 250 W TV set in 1 hour or a 1200 W toaster in 10 minutes?
उत्तर
Energy consumed by the TV set,
E `=pxxt`
`= 250xx1` = 250 Wh
Energy consumed by the toaster,
E `=pxxt`
`= 1200 Wxx10/60h (10 min=10/60h)`
= 200 Wh
Thus, it is clear that the TV set consumes more electrical energy.
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