Question

A Pendulums completes 2 oscillations in 5 s. (a) What is its time period?

(b) If g = 9.8 $m{s}^{-2}$, find its length.

Answer 1

Given: oscillations = 2

(a) Time period $=1/oscillationspersecond$

$=\frac{1}{2÷5}=\frac{5}{2}=2.5s$

(b)We know, T = $2\pi \sqrt{\frac{1}{g}}$

$\therefore$ Length of pendulum,

$1=\frac{g{T}^2}{4{\pi }^2}$

$=\frac{9.8\times (2.5{)}^2}{4\times (3.14{)}^2}$

$=1.55m$