Q. The vertical extension in a light spring by a weight of $1\ kg$ suspended from the wire is $9.8\ cm.$ The period of oscillation
A) $20\pi s$
B) $2\pi s$
C) $2\pi/10s$
D) $200\pi s$
Explanation
(c) $\because mg = kx \Rightarrow \frac{m}{k} = \frac{x}{g} \Rightarrow T = 2\pi\sqrt{\frac{m}{k}} = 2\pi\sqrt{\frac{x}{g}}$
$= 2\pi\sqrt{\frac{9.8 \times 10^{- 2}}{9.8}} = \frac{2\pi}{10}\ s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.