Question

A simple pendulum is suspended from the roof of a train. If the train is moving with an acceleration of 49 cm/s² , then the angle of inclination of the string about the vertical will be ____.

 a) 20°  

 b) 0°   

 c) 30°

 d) 3°

Answer 1

pseudo force=ma

gravity=mg

tan$\theta =\frac{ma}{mg}$

$\theta =ta{n}^{-1}(\frac{ma}{mg})$

$=ta{n}^{-1}(\frac{0.49}{9.8})$

$=ta{n}^{-1}(0.05)$

=$3^o$