Water falls from a height of $210\,m.$ Assuming whole of energy due to fall is converted into heat the rise in temperature of water would be   ………. $^oC$  $(J = 4.3 \,Joule/cal)$

Heat required to convert one gram of ice at $0°C$ into steam at $100°C$ is $($given $L_{steam}$ $= 536\, cal/gm)$

A piece of metal of mass $5\ kg$ and temperature $-50\ ^oC$ is dropped in $20\  kg$ water at $52\ ^oC$ temperature. In thermal equilibrium temperature of water decreases by $2\ ^oC$, then specific heat of metal is …… $ Cal/g\,^oC$

If earth suddenly stops rotating about its own axis, the increase in it’s temperature will be

If two balls of same metal weighing $5\, gm$ and $10\, gm$ strike with a target with the same velocity. The heat energy so developed is used for raising their temperature alone, then the temperature will be higher