Solved UPSC CDS/OTA Question
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Q · Current ElectricityMedium · 45s
Which one is used to vary the current in a circuit? Option: 49
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.
A rheostat is a variable resistor.
49
Final Answer: Option B — Rheostat
49