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NUMERICALS, 1., , 10 g of ice at 0°C absorbs 5460 J of heat energy to melt, and change to water at 50°C. Calculate the specific, latent heat of fusion of ice. Specific heat capacity of, water is 4200 J kg! K'. Ans. 336 J gHow much heat energy is released when 5-0 g of water, at 20°C changes into ice at 0°C ? Take specific heat, capacity of water = 4-2 J g' K™', specific latent heat, of fusion of ice = 336 J g!. Ans. 2100 J, A molten metal of mass 150 g is kept at its melting, point 800°C. When it is allowed to freeze at the same, temperature, it gives out 75,000 J of heat energy., , (a) What is the specific latent heat of the metal ?, , (b) If the specific heat capacity of metal is, 200 J kg“! K~!, how much additional heat energy, will the metal give out in cooling to — 50 °C ?, , Ans. (a) 500 J g™, (b) 25,500 J, , A refrigerator converts 100 g of water at 20°C to ice, , at— 10°C in 73-5 min. Calculate the average rate of heat, , extraction in watt. The specific heat capacity of water is, , 4-2 g-'K“, specific latent heat of ice is 336 J g-! and, , the specific heat capacity of ice is 2:1 Jg1K-., , Ans. 10W, , In an experiment, 17 g of ice is used to bring down the, , temperature of 40 g of water at 34°C to its freezing