Login/Sign Up
Home » A cylindrical conductor of length l and uniform area of cross section A has resistance R. Another conductor of length 2l and resistance R of the same material has an area of cross-section (a) A/2 (b) 3A/2 (c) 2A (d) 3A
A cylindrical conductor of length l and uniform area of cross section A has resistance R. Another conductor of length 2l and resistance R of the same material has an area of cross-section
(a) A/2
(b) 3A/2
(c) 2A
(d) 3A
CBSE | Class 10 | Electricity | NCERT Exemplar | Science
A cylindrical conductor of length l and uniform area of cross section A has resistance R. Another conductor of length 2l and resistance R of the same material has an area of cross-section
(a) A/2
(b) 3A/2
(c) 2A
(d) 3A

Solution: Answer is (c) 2A

Explanation:

We are well aware of this.

R is equal to (L/A).

The resistance of a wire of length L is denoted by
The area of the cross-section is denoted by the letter A.
The length of the resistance is directly proportional to the resistance, whereas the area of the cross-section is inversely proportional to the length of the resistance.

As a result, when the length is doubled, i.e., 2L, the resistance will be doubled, resulting in 2R.

To keep the resistance constant, the area of the cross-section should be doubled as 2A in order to maintain the same resistance as R.

i

More Material