Question

A lift is ascending with acceleration g/3.What will be the time period of a simple pendulum suspended from the ceiling, if its time period in stationary lift is T?

Answer 1

here we use concept of pseudo force
so , acceleration of lift with respect to ground (a)=(g+g/3)=4/3g
now
formula of time period of pendulum(T)
=2pi.root(L/a)
T'=2pi.root (L/4/3g)=2pi.root (3L/4g)
T'=root (3/4) T