When the pendulum is oscillating over a current carrying coil, and when the direction of oscillating pendulum bob is opposite to the direction of current. Its instantaneous acceleration increases. Hence time period T<2πgℓ and damping is larger than in air alone due energy dissipation.
Bob of a simple pendulum of length l is made of iron. The pendulum is oscillating over a horizontal coil carrying direct current. If the time period…
JEE Main 2013 — Physics Waves & Oscillations
2013mcqeasy
Bob of a simple pendulum of length l is made of iron. The pendulum is oscillating over a horizontal coil carrying direct current. If the time period of the pendulum is T then :
Official previous-year question
Held on 23 Apr 2013 · Verified 6 Jul 2026.
Options
- A
T<2πgl and damping is smaller than in air alone.
- B
T=2πgl and damping is larger than in air alone.
- C
T>2πgl and damping is smaller than in air alone.
- D
T<2πgl and damping is larger than in air alone.
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