Two heated wires of the same dimensions are first connected in series and then it’s parallel to a source of supply. What will be the ratio of heat produced in the two cases?
Two heated wires of the same dimensions are first connected in series and then it’s parallel to a source of supply. What will be the ratio of heat produced in the two cases?

Ans: It is known that,

    \[\begin{array}{l} H=I^{2} R t \quad\left(I=\frac{V}{R}\right) \\ \Rightarrow H=\frac{V^{2}}{R^{2}} \times R \times t \\ \Rightarrow H=\frac{V^{2}}{R} t \\ \Rightarrow H \propto \frac{1}{R} \\ H_{g x i g s}=\frac{R}{R_{\text {paralle1 }}} \\ \Rightarrow \frac{R_{\text {seriss }}}{\left(\frac{1}{R}+\frac{1}{R}\right)} \\ R+R \end{array}\]

Therefore, the ratio of heat produced is 1: 4.