Question

The lengths of two copper wires A and B are 180 cm and 270 cm respectively. If the mass of wire A is twice the mass of wire B and the electrical resistance of wire A is \(200\Omega\), then the electrical resistance of wire B is:

• A. \(900\Omega\)
• B. \(400\Omega\)
• C. \(600\Omega\)
• D. \(300\Omega\)

Hint:

For wires of the same material: \[ R\propto \frac{L^2}{m}. \] This shortcut saves a lot of calculation.

Answer 1

The Correct Option is A