ExamBro
ExamBro
CUET · PHYSICS · PYQ PAPER 2023

A metal rod of length 10 cm and a rectangular cross-section 1cm * 1/2 cm is connected to a battery across opposite faces. The resistance will be :

  1. A maximum when the battery is connected across \(1 cm * 1 / 2 cm\) faces.
  2. B maximum when the battery is connected across \(10 cm \times 1 cm\) faces.
  3. C maximum when the battery is connected across cm faces. \(10 cm^* 1 / 2\)
  4. D same irrespective of the three faces
Verified Solution

Answer & Solution

Correct Answer

(A) maximum when the battery is connected across \(1 cm * 1 / 2 cm\) faces.

Step-by-step Solution

Detailed explanation

\(R = \rho \frac{L}{A}\) Case 1 (across \(1 \text{ cm} \times 1/2 \text{ cm}\) faces): \(L = 10 \text{ cm}\), \(A = 1 \text{ cm} \times 0.5 \text{ cm} = 0.5 \text{ cm}^2\) \(R_1 = \rho \frac{10}{0.5} = 20\rho\) Case 2 (across \(10 \text{ cm} \times 1 \text{ cm}\) faces):…