A household refrigerator with a coefficient of performance $1.2$ removes heat from the refrigerated space at the rate of $60\ kJ/min$ .What would be cost of running this fridge for one month $\mathrm{Rs.}$ ..................... $(30\ days)$ (assuming each day it is used for $4$ hours and cost of one electrical unit is $6$ Rs.)
A$180$
B$300$
C$480$
D$600$
Diffcult
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D$600$
d $W=\frac{\phi C}{c o p}=\frac{60 \times 10^{3}}{60 \times 1.2} \mathrm{J} / \mathrm{s}=\frac{10^{3}}{1.2} \mathrm{J} / \mathrm{s}$
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