When lift is stationary
T=2πgL
When lift is moving upwards
⇒ Pseudo force acts downwards
⇒geff=g+2g=23g
⇒ New time period
T′=2πgeffL=2π3g2L
T′=32T
JEE Main 2021 — Physics Waves & Oscillations
Time period of a simple pendulum is T inside a lift when the lift is stationary. If the lift moves upwards with an acceleration 2g, the time period of pendulum will be :
Held on 16 Mar 2021 · Verified 6 Jul 2026.
3T
3T
23T
32T
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