Question

If $20$gm of water at ${50}^o$C is mixed with $60$g of water at ${10}^o$C. Then calculate the final temperature of the mixture.

Answer 1

Let final temperature be $T$

Heat loss = Heat gain

$20\times S_{water}\times (50-T)=60\times S_{water}\times (T-10)\Rightarrow 20\times 1\times (50-T)=60\times 1\times (T-10)\Rightarrow 50-T=3T-30\Rightarrow 4T=80\Rightarrow T=20℃$