(N/A) Joule's heating effect states that when an electric current $I$ flows through a conductor of resistance $R$ for time $t$,the heat $H$ produced is given by the formula $H = I^2Rt$.
Experimental demonstration: Connect a resistor of known resistance $R$ in series with an ammeter,a battery,and a plug key. Connect a voltmeter in parallel across the resistor. Measure the current $I$ and potential difference $V$ across the resistor. The heat produced can be calculated by measuring the temperature rise in a known mass of water or by using the formula $H = VIt$.
Applications in daily life:
$1$. Electric iron
$2$. Electric toaster
$3$. Electric heater
$4$. Electric kettle