Question
A
kettle, when connected to a 220V d.c. supply, boils 1 litre of water from 11°C in 3.5 min. Calculate the percentage time difference
when the water
is boiled, by connecting the kettle to a 220V, 50Hz a.c. supply. The inductance of the
element of 0.05H. Take 1 litre of water to
have a mass
of lkg
and its specific heat capacity as
4.2kJ/kg°C.
