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## What is centripetal force?

What is centripetal force?

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Answer

Centripetal fforce is the net force to be acting on a body so that it can move in a curved path. The centripetal force is always directed towArds the center of the circular path. The word centripetal means “directed towards the center” or “center seeking force”.

Please remember that it is not a new kind of force, but in different case one or more of the fundamental forces or their components provide the necessary centripetal for e.

The magnitude of the centrifugal force that must be acting on a body of mass m moving with a speed v along a curve of radius of curvature r is given by F = mv^2/r

## Bouncing ball and energy dissipation problem

Please help me with the question below.. I’m totally confused!

A player throws a ball of mass 0.6 kg into the air, to a height of 4.0 m above the ground. The ball then falls to the ground. During the impact, 22% of the ball’s energy is lost. Calculate the height to which the ball rises after the bounce. Your assistance will be appreciated..

**Mustafa posted**

Answer:

m= 0.6 kg

h = 4.0 m

Energy = mgh

During impact 22% energy is lost. Therefore, energy remaining = 88%

Therefore the energy with which the ball rebounds = 24 x 88/100 J

This is equal to the potential energy at the highest point after bouncing

If the new height is h’

mg h’ = 88% mgh

h’ = 0.88 x h = 0.88 x 4.0 =**3.52 m**

If you have further doubts, please ask

###### Related articles

- Calculate velocity and direction of a ball to ball collision based on mass and bouncing coefficient (stackoverflow.com)
- Rainfall Dissipates Energy via Friction with Air (scientificamerican.com)

## Momentum and Kinetic Energy

How it is possible to double the momentum of a body by increasing the kinetic energy four times?at the time what happen to mass?

Answer:

When we say, KE is increased, we mean to say by increasing speed alone unless otherwise specified.

Here mass remains constant.

Please note that the question says, KE **of a body** increased 4 times; which suggests that the body is the same and KE is increased by increasing the speed alone.

## Limitations of Homogenity

Paraser asked

“What are the limitations of homogenity?”

The question is acutually”**What are the limitations of dimensional analysis**?”

The dimensional analysis is based on the **principle of homogenity** of dimensions. The question is already discussed earlier ** HERE**