Question

Find the ratio of the lengths of the two mathematical pendulums, if the ratio of periods is 1.5​

Answer 1

Answer:

The ratio of lengths of the two mathematical pendulums is 9:4.

Explanation:

It is given that,

The ratio of periods of two pendulums is 1.5

Let the lengths be L₁ and L₂.

The time period of a simple pendulum is given by :

$T=2\pi \sqrt{\dfrac{l}{g}}$

or

$T^2=4\pi^2\dfrac{l}{g}\\\\l=\dfrac{T^2g}{4\pi^2}$

Where

l is length of the pendulum

$l\propto T^2$

or

$\dfrac{l_1}{l_2}=(\dfrac{T_1}{T_2})^2$ ....(1)

ATQ,

$\dfrac{T_1}{T_2}=1.5$

Put in equation (1)

$\dfrac{l_1}{l_2}=(1.5)^2\\\\=\dfrac{9}{4}$

So, the ratio of lengths of the two mathematical pendulums is 9:4.