Q. When a mass $m$ is attached to a spring, it normally extends by $0.2\ m.$ The mass $m$ is given a slight addition extension and released, then its time period will be
A) $\frac{1}{7}\sec$
B) $1\ sec$
C) $\frac{2\pi}{7}\pi$
D) $\frac{2}{3\pi}\ sec$
Explanation
(c) $Kx = mg \Rightarrow \frac{m}{K} = \frac{x}{g}$
So$\ T = 2\pi\sqrt{\frac{m}{K}} = 2\pi\sqrt{\frac{x}{9}} = 2\pi\sqrt{\frac{0.2}{9.8}} = \frac{2\pi}{7}s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.