How many calories of heat will be produced approximately in a $210\, watt$ electric bulb in $5$ minutes .............. $cal $
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(d) $H = \frac{{{V^2}t}}{{R \times J}}\,Calories = \frac{{P\,t}}{J} = \frac{{210 \times 5 \times 60}}{{4.2}} = 15000\,cal$
(d) $H = \frac{{{V^2}t}}{{R \times J}}\,Calories = \frac{{P\,t}}{J} = \frac{{210 \times 5 \times 60}}{{4.2}} = 15000\,cal$
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