Question

Two wires of the same dimensions but resistivities $p_1$ and $p_2$ are connected in series.The equivalent resistivity of the combination is

• A. $p_1+p_2$
• B. $\frac{p_1+p_2}{2}$
• C. $\sqrt{p_1{p}_2}$
• D. $2(p_1+p_2)$

Answer 1

The correct option is A $p_1+p_2$

$R\propto \rho$ ( l and A same resistors)

Resistance is proportional to resistivity .In series effective resistance = $R_1+R_2$ So we can say that equivalent resistivity

$\rho ={\rho }_1+{\rho }_2$