A piece of wire of resistance R is cut into five equal parts. These parts are then connected in parallel. If the equivalent resistance of this combination is R′, then the ratio R/R′ is _____. (a) 1/25 (b) 1/5 (c) 5 (d) 25
ScienceClass 10CBSEAnswered 27 Mar 2026
Answer
Solution:
Answer: d) 25
Explanation:
The resistance is cut into five equal parts, which means that the resistance of each part is R/5.
We know that each part is connected to each other in parallel, hence the equivalent resistance can be calculated as follows:
The ratio of R/R′ is 25.
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