posted by christ on .
An electric kettle contains 1.5 kg of water at
C and powered by a 2.0 kW electric element. If the thermostat of the kettle fails to operate, approximately how long will it take for the kettle boil dry? (Take the specific latent heat of vaporization of water as
Q = rm= 2•10⁶•1.5=3•10⁶ J
t=Q/P= 3•10⁶/2•10³=1500 s=25 min=0.42 h