Question

The horizontal velocity to be given to the bob of a simple pendulum of length 100cm. So that it
makes just one revolution is [ ]
a) 3.5 ms–1 b) 7 ms–1 c) 14 ms–1 d) 28 ms–1

Answer 1

Answer:

Given:

A simple pendulum is provided. The length of string is 100 cm.

To find:

Minimum velocity to be given to Bob for completing just one revolution .

Concept:

The basic aim is to make the Bob cross the highest point of the vertical circle in order to complete the whole revolution.

For that the Bob and string must not become loose at the highest position.

Once the Bob crosses that point , it again gains velocity due to gravity and cones down following a circular trajectory.

Calculation:

For any vertical circle of radius r to operate , the minimum velocity that has to be provided at bottom position is :

$v = \sqrt{5 \times g \times r}$

Putting all the available values , considering g (Gravitational acceleration ) = 10 m/s² and radius to be 1 m (100 cm)

$= > v = \sqrt{5 \times 10 \times 1}$

$= > v = \sqrt{50}$

$= > v = 7 .07 \approx7\: m {s}^{ - 1}$

So final answer is :

$\boxed{ \red{ \huge{ \bold{v = 7 \: m {s}^{ -1 } }}}}$

Answer 2

$</p><p>\huge{\tt{\pink{Hello!!! }}}$

$</p><p>\huge{\fbox{\fbox{\rightarrow{\mathfrak {\green{QUESTION \: - }}}}}}$

The horizontal velocity to be given to the bob of a simple pendulum of length 100cm.

The minimum velocity of the bob so that itmakes just one revolution is :

• a) 3.5 ms–1

• b) 7 ms–1 √√√

• c) 14 ms–1

• d) 28 ms–1

__________________________

$\huge{\fbox{\fbox{\rightarrow{\mathfrak {\green{</strong><strong>ANSWER</strong><strong> \: - }}}}}}$

A simple pendulum is given

A simple pendulum is given The length of the string is 100 cm.

To find : Minimum Velocity is Bob to Complete One Oscillation.

Formula Used :

V = √( 5 × g × r ) = 7.07 m/s^2 = 7 m/s^2 approx.

$</p><p>\huge{\tt{\pink{Final \: Answer \:is \: 7 m/s^2 }}}$

$</p><p>\huge{\tt{\pink{\therefore{Option \: D \: Is \: Correct. }}}}$