MCQ
A pendulum is swinging in an elevator. Its period will be greatest when the elevator is
- Amoving upwards at constant speed
- Bmoving downwards
- Cmoving downwards at constant speed
- ✓accelerating downwards
✓
Answer
Correct option: D.
accelerating downwards
d
Time period of a simple pendulum is given by
Time period of a simple pendulum is given by
$T=2 \pi \sqrt{\frac{l}{g}}$ or $T \propto \sqrt{\frac{l}{g}}$
when the elevator is accelerating downwards, the net gravitational acceleration is $(g-a),$ so, the time period when elevation is accelerating downwards, is greatest.
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