Physics

Problem

50\,\text{g}

sample of water at

80^{\circ}\text{C}

is poured into an insulated cup containing

100\,\text{g}

of water at

20^{\circ}\text{C}

. The specific heat capacity of liquid water is

4.18\,\text{J}\,\text{g}^{-1}\,^{\circ}\text{C}^{-1}

. Determine the final temperature of the mixture once thermal equilibrium is reached. Assume no heat is lost to the surroundings.