Two wires A and B of the same material have their lengt

SOLUTION

Let Length of wires A and B be x and 2x
Let Area of cross -section A and B be 2y and 3y respectively.
For wire A,
$12=\frac{\rho \times x}{2y}\Rightarrow 24=\frac{\rho \times x}{y}And,R_B=\frac{\rho \times 2x}{3y}=24\times \frac{2}{3}=16\Omega$