Question

A pendulum Bob released from some initial height such that the speed of the bob at the bottom of the swing is 1.9m/s. What is the initial height of the bob?

Answer 1

Answer:

h = 18.4 cm

Explanation:

Given that,

The speed of the bob at the bottom of the swing is 1.9m/s.

We need to find the initial height of the bob. Let it is h.

We can find it using the conservation of energy i.e.

$mgh=\dfrac{1}{2}mv^2$

Where

v is speed of the bob

So,

$h=\dfrac{v^2}{2g}\\\\h=\dfrac{(1.9)^2}{2\times 9.8}\\\\h= 0.184\ m$

or

h = 18.4 cm

So, the initial height of the bob is 18.4 cm.