Water of volume 2 litre in a container is heated with a coil of 1 kW at

PHYSICS · Single correct · A Level · Physics · Further mechanics and thermal physics · Further mechanics and thermal physics

Problem

27^\circ\text{C}

. The lid of the container is open and energy dissipates at rate of 160 J/s. In how much time temperature will rise from

27^\circ\text{C}

77^\circ\text{C}

[Given specific heat of water is

4.2\ \text{kJ/kg}

] (1) 7 min (2) 6 min 2 s (3) 8 min 20 s (4) 14 min