What would be the difference in temperature of water above and below a waterfall 200 meters high if we assume that the whole of the potential energy lost is converted into heat energy in water ?

What we call a device for converting heat energy into work.

A water fall discharges 60 litres of water per sec from a vertical height of 200 m . Assuming that all the energy due to fall is converted to heat and is retained by the falling water , find (i) the quantity of heat produced per sec and (ii) rise in temperature of water .

The mechanical device which converts heat energy into mechanical energy , what we call it?

One gm of water at 373 K is converted into steam at the same temperature. The volume of 1 c .c of water becomes' 1671 c.c on boiling. Calculate the change in internal energy of the system if heat of vaporisation of water is 5.4xx10^5calkg^-1 .

A pond is covered by a sheet of ice 2.0 cm thick (thermal conductivity 1.6 jm^(-1)s^(-1)k^(-1) . The temperature of the lower surface of ice is 0^@ C and that of the upper surface is -10^@ C . At what rate is heat conducted through each square meter of the ice ? What is the direction of this flow of energy ?