Question

On a winter day the temperature of the tap
water is 20°C whereas the atmospheric
temperature is 5°C. Water is stored in a tank
of capacity 0.5 m for household use. If it
were possible to use the heat liberated by the
water to left a 10 kg mass vertically. How
high can it be lifted as the water comes to
the room temperature. Take g = 10 ms - ??
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Answer 1

As the water comes to its room temperature, it liberates energy and this energy is utilized in increasing the potential energy of the mass

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