Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Current Electricity

Question:

A metal rod of length 10 cm and a rectangular cross-section of 1 cm x 1/2 cm is connected to a battery across opposite faces. Which of the following is true about its resistance?

Options:

maximum when the battery is connected across 10 cm x 1/2 cm faces

maximum when the battery is connected across 1 cm x 1/2 cm faces.

maximum when the battery is connected across 10 cm x 1 cm faces.

 same irrespective of the three faces.

Correct Answer:

maximum when the battery is connected across 1 cm x 1/2 cm faces.

Explanation:

The maximum resistance will be achieved when the value of 1/A , is maximum, so that ‘A’ must be minimum and it is minimum when area of cross section is 1 cm x 1/2cm