Solved UPSC CDS/OTA Question
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Q · Current ElectricityMedium · 45s
Resistance of a wire is 10 ohms. If its length is doubled and area is halved, what will be the new resistance? Option: 38
TopicCurrent Electricity
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
R∝lAR∝Al. New R = 10 × (2/0.5) = 40 ohms.
38
Final Answer: Option B — 40 ohms
38