Question

A seconds pendulum is suspended from the roof of a bus. The time period of oscillation when the bus is moving along a straight horizontal road with uniform acceleration is

• A. 2 s
• B. < 2 s
• C. > 2 s
• D. 0

Answer 1

The correct option is B < 2 s

when a bus is moving horizontally $a_{eff}=\sqrt{a^2+g^2}$
$\therefore T=2\pi \sqrt{\frac{l}{a_{eff}}}$
as $a_{eff}$ increases T decreases
$\Rightarrow T<2s$