JEE AdvancedPhysicsHeat and ThermodynamicsMCQ+3 / −1
A water cooler of storage capacity 120 litres can cool water at a constant rate of P watts. In a closed circulation system (as shown schematically in the figure), the water from the cooler is used to cool an external device that generates constantly 3 kW of heat (thermal load). The temperature of water fed into the device cannot exceed 30°C and the entire stored 120 litres of water is initially cooled to 10°C. The entire system is thermally insulated. The minimum value of P (in watts) for which the device can be operated for 3 hours is : 
(Specific heat of water is 4.2 kJ kg−1 K−1 and the density of water is 1000 kg m−3)
(Specific heat of water is 4.2 kJ kg−1 K−1 and the density of water is 1000 kg m−3)- A1600
- B2067
- C2533
- D3933
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