A piece of iron of mass 2.0 kg has a heat capacity of 966 J K^-1 . Find (i) heat energy needed to warm it by 15° C, and (ii) it's specific heat capacity in S.I unit.

Calculate the amount of heat energy required to raise the temperature of 200 g of copper from 20°C to 70°C. Specific heat of capacity of copper = 390 J kg^-1 K^-1

A car's cooling system uses water to absorb heat from the engine. If 5 kg of water absorbs 420 kJ of heat, what is the temperature increase of water? (Specific heat capacity of water = 4200 J kg⁻¹ K⁻¹)

Find the time taken by a 500 W heater to raise the temperature of 50 kg of material of specific heat capacity 960 J kg^-1 K^-1, from 18°C to 38°C. Assume that all the heat energy supplied by heater is given to the material.