1. Centripetal Force and Centrifugal Force
Centripetal Force and Centrifugal Force. Newton's Universal Law of Gravitation
By Corina Bot

2. Centripetal Force - The Real Force
cars are forced through a loop by the track applying a centripetal force on them.
The reactive centrifugal force of the cars, associated with their inertia, holds them on the track

3. Centripetal Force - The Real Force
Definition:
Centripetal  Latin for "center seeking“
Centripetal force is a center seeking force => the force is always directed toward the center of the circle and orthogonal to the velocity of the body.
Using centripetal acceleration definition
From Newton’s 2nd law
We have centripetal force

4. Centripetal Force - The Real Force – Examples:
The smaller the velocity of the object, the less centripetal force you will have to apply.
The smaller the length of rope (radius), the more centripetal force you will have to apply to the rope.
Notice that the centripetal force and the centripetal acceleration are always pointing in the same direction.

5. Centrifugal Force – The False Force
Definition:
Centrifugal  Latin for "center fleeing“
Centrifugal force ("fictitious" force) represents the effects of inertia that arise in connection with rotation
 It is experienced as an outward force away from the center of rotation.
Centrifugal force example - cars driving on a wall

6. Newton's law of universal gravitation
Every point mass attracts every other point mass by a force pointing along the line intersecting both points.
The force is directly proportional to the product of the two masses and inversely proportional to the square of the distance between the point masses.
F = the magnitude of the gravitational force between the two point masses,
G = the gravitational constant,
m1 = the mass of the first point mass,
m2 = the mass of the second point mass, and
r = the distance between the two point masses.