Physics - SHM Question with Solution | TestHub

The time period of a simple pendulum is given by $T=2\pi \sqrt{\frac{l}{g_{eff}}}$.

When the point of suspension is moved vertically upward with an acceleration $a$, the effective acceleration due to gravity becomes $g_{eff}=g+a$.

Since $g_{eff}>g$, the time period $T$ decreases.

Answer: decreases