Calculate the time required to heat 20 kg of water from 10∘C to 35∘C using an immersion heater rated 1000 W. Assume that 80% of the power input is used to heat the water. Specific heat capacity of water =4200 J kg−1K−1.
Heat is supplied at the same rate to equal masses of ice and water at the melting point (MP) of ice. Calculate the ratio of the time required to melt the ice and to bring the water to its Boiling Point. [Given that specific heat capacity of water = 4.2 J/goC, Specific latent heat of ice = 336 J/g]