Morning breakfast gives $5000 \,cal$ to a $60 \,kg$ person. The efficiency of person is $30 \%$. The height upto which the person can climb up by using energy obtained from breakfast is ……… $m$

A $20 \,g$ bullet whose specific heat is $5000 \,J kg ^{\circ} C$ and moving at $2000 \,m / s$ plunges into a $1.0 \,kg$ block of wax whose specific heat is $3000 \,J kg ^{\circ} C$. Both bullet and wax are at $25^{\circ} C$ and assume that $(i)$ the bullet comes to rest in the wax and $(ii)$ all its kinetic energy goes into heating the wax. Thermal temperature of the wax $\left(\right.$ in $\left.^{\circ} C \right)$ is close to

A continuous flow water heater (geyser) has an electrical power rating $= 2 \,\,kW$ and efficienty of conversion of electrical power into heat $ = 80 \%$. If water is flowing through the device at the rate of $100 \,\,cc/sec$, and the inlet temperature is $10^o C$, the outlet temperature will be ……. $^oC$ 

A calorimeter contains $0.2\, kg$ of water at $30\,^oC$, $0.1\,kg$ of water at $60\,^oC$ is added to it, the mixture is well stirred and the resulting temperature is found to be $35\,^oC$. The thermal capacity of calorimeter is ………. $J/K$

An experiment takes $10\, minutes$ to raise the temperature of water in a container from $0\,^oC$ to $100\,^oC$ and another $55\, minutes$ to convert it totally into steam by a heater supplying heat at a uniform rate . Neglecting the specific heat of the container and taking specific heat of water to be $1\, cal / g\,^oC$, the heat of vapourization according to this experiment will come out to be …….. $cal/g$