0.1 ~m ^3 of water at 80^ C is mixed with 0.3 ~m ^3 of water at 60^ C . The final temperature of the mixture is

Step-by-step solution

Let the final temperature of mixture be t . Heat lost by water at 80^ C =m s t=0.1 10^3 s_ water (80^ -t ) ( m=V d=0.1 10^3 ~kg ) Heat gained by water at 60^ C =0.3 10^3 s_ water (t-60^ ) According to principle of calorimetry Heat lost = Heat gained 0.1 10^3 s_ water (80^ -t )=0.3 10^3 s_ water (t-60^ ) or (80^ -t )=3 (t-60^ ) or 4 t=260^ or t=65^ C