10 litres of hot water at 70^(@)C is mixed with an equal volume of cold water at 20^(@)C. Find the resultant temperature of the water. (Specific heat of water = 4200 J/Kg K)

10 litres of hot water at 70^(@)C is mixed with an equal volume of col

1.	10 litres of hot water at 70^(@)C is mixed with an equal volume of cold water at 20^(@)C. Find the resultant temperature of the water. (Specific heat of water = 4200 J/Kg K)
Answer» Solution :Resultant TEMPERATURE, t = `(m_(1)s_(1)t_(1)+m_(2)s_(2)t_(2))/(m_(1)s_(1)+m_(2)s_(2))`. Here, `m_(1)=m_(2)=10kg`, since mass of 1 litre of water is 1 kg. `t_(1)=70^(@)C,t_(2)=20^(@)C` and `s_(1)=s_(2)=4200J//kgK` `t=(10xx4200xx70+10xx4200xx20)/(10xx4200+10xx4200)=45^(@)C`.