Question

stone boiling is a method of cooking that has been used throughout the world, especially before the introduction of heat-resistant vessels(such as ceramics). It involves dropping "red- hot" stones into a container of water it boils. Suppose a 0.4 kg stone at 300 C is dropped into a vessel containing 10 litres of water at 20 C. Neglecting heat transfer to the container, what is the final temperature of the stone and water? [ Take the specific heat of this particular stone = 1200 J kg^-1]

Answer 1

Given ,

Mass of stone = 0.4 kg , temp. of stone = 300 C , specific heat capacity of stone = 1200 J/kg^-1

Mass of water = 10 litre = 10 kg , temp of water = 20 ⁰C , Specific heat cpacity of water = 4200 j /kg^-1

Let the final temperature be T ^oC .

Heat loss by stone = Heat gain by water

m_{stone * Sstone}* delta (T) _stone = m_water * S_water * delta(T) _water

0.4*1200*(300-T) = 10 * 4200 * (T- 20)

on solving this equation , you will get the value of T = 23.16 ⁰C