Question

A person wanted to have a warm bath at 40°c and placed 5.0kg of water in a basin at 85°c. What mass of cold water at 25°c must be added to the hot water to obtain the choice of bath. Neglecte heat losses and take specific heat capacity of water as 4200J/ kg/ k

Answer 1

$cm_1(85°-40°)=cm_2(40°-25°)\to$

$45°m_1=15°m_2\to m_2=3m_1=3\cdot5=15\ (kg)$ . Answer