(a) A wire of resistance R is cut into three equal parts. If these three parts are then joined in parallel, calculate the total resistance of the combination so formed. OR (b) Define electric power. When do we say that the power consumed in an electric circuit is 1 watt?

(a) Let the resistance of each part be $R'$, then $R' = \frac{R}{3}$. When these three parts are joined in parallel, the total resistance of the combination so formed is $R_{eq} = \frac{R'}{3} = \frac{R}{9}$.<hr/>(b) Electric power is defined as the rate at which electric work is done or the rate at which electric energy is consumed by an electric circuit. When the work done in an electric circuit is 1 joule per second, we say that the power consumed in the electric circuit is 1 watt.