<p>(a) An electric iron consumes energy at a rate of 880 W when heating is at the maximum rate and 330 W when the heating is at the minimum. If the source voltage is 220V, calculate the current and resistance in each case.</p>

<p>(b) What is heating affect the electric current?</p>

<p>(c) Find an expression for the amount of heat produced, when a current passes through a resistance for some time.</p>