Water of volume $2$ litre in a container is heated with a coil of $1\,kW$ at $27\,^\circ C$. The lid of the container is open and energy dissipates at rate of $160\,J/s.$ In how much time temperature will rise from $27\,^\circ C$ to $77\,^\circ C$ [Given specific heat of water is $4.2\,kJ/kg$]

During illness an $80\, kg$ man ran a fever of $102.2^o F$ instead of normal body temperature of $98.6^o F$. Assuming that human body is mostly water, how much heat is required to raise his temperature by that amount  ………. $kcal$ 

A liquid of mass m and specific heat $c$ is heated to a temperature $2T.$ Another liquid of mass $m/2$ and specific heat $2c$ is heated to a temperature $T.$ If these two liquids are mixed, the resulting temperature of the mixture is

Why the land of desert gets hotter in day time and colder in night time quickly ?

A hammer of mass $1kg$ having speed of $50 \,m/s$, hit a iron nail of mass $200\, gm.$ If specific heat of iron is $0.105\, cal/gm°C$ and half the energy is converted into heat, the raise in temperature of nail is…….. $^oC$