JEE Main 2012 — Oscillations Question with Solution
JEE Main 2012 (Offline)
Question
If a simple pendulum has significant amplitude (up to a factor of of original) only in the period between to , then may be called the average life of the pendulum. When the spherical bob of the pendulum suffers a retardation (due to viscous drag) proportional to its velocity, with '' as the constant of proportionality, the average life time of the pendulum is (assuming damping is small) in seconds:
Choose an option
Show full solutionCorrect option: D
Correct answer
D
Step-by-step explanation
As retardation retarding force net restoring torque when angular displacement is is given by where, for small damping, the solution of the above differential equation will be angular amplitude will be According to question, in time (average life-time), angular amplitude drops to value of its original value
Practice this on the real CBT interface
Solve this JEE Main question (and the rest of the Oscillations chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.
Solve interactively →About this question
This is a previous-year question from JEE Main 2012, covering the Oscillations chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.