Physics · 2025
JEE Main · 29 January 2025, Shift 1 · Q37
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Choke coil is simply a coil…
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Choke coil is simply a coil having a large inductance but a small resistance. Choke coils are used with fluorescent mercury-tube fittings. If household electric power is directly connected to a mercury tube, the tube will be damaged.
Reason (R) : By using the choke coil, the voltage across the tube is reduced by a factor $\displaystyle \left(\mathrm{R} / \sqrt{\mathrm{R}^2+\omega^2 \mathrm{~L}^2}\right)$, where $\displaystyle \omega$ is frequency of the supply across resistor R and inductor L. If the choke coil were not used, the voltage across the resistor would be the same as the applied voltage.
In the light of the above statements, choose the most appropriate answer from the options given below :
Official answer
From NTA’s final answer key for this paper.
(4)
Both (A) and (R) are true and (R) is the correct explanation of (A)
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.