Question

22. If the length of the wire increased to two times. What will be the
change in resistivity? Give reason.
I
23. A 0 ohm resistance is cut into three equa parts and conneoted in
paralle Find the equivalent resistance of the combination​

Answer 1

Answer:

Explanation:

22. The resistance of a conductor is directly proportional to its length (L) as R ∝ L. Thus doubling its length will double its resistance, while halving its length would halve its resistance. Also the resistance of a conductor is inversely proportional to its cross-sectional area (A) as R ∝ 1/A.

23. As 9 Ohm cut down in 3 equal parts.

It means Resistance of each wire = 3 Ohm

We know,

Parallel Equivalent Resistance  

1/r = 1/3 + 1/3 + 1/3

1/r = 3/3

1/r = 1 Ohm   ← (Ans)