Centripetal Force:
When a body revolves in a circular path, it has an acceleration directed toward the centre. We know that no acceleration is possible without a force. The body must, therefore, be acted upon by a force in the inward direction.
The inward force on the body moving in a circular path is called centripetal force.
To find the magnitude of the centripetal force, we recall that according to the second law of motion-
| Force = mass x acceleration |
Since the centripetal acceleration ac has a magnitude-
| ac = ν2/R |
Where ν is the speed and R is the radius of the path, the centripetal force Fc is given by-
| Fc = mν2/R |
Where m is the mass of the body.
It is to be noted that the centripetal force is not a new kind of force but it is the name given to that force that is responsible for keeping the body in the circular motion. Thus, when we revolve a stone attached to a string, the centripetal force is an elastic force. Planets move in nearly circular orbits around the sun and the necessary centripetal force is provided by the gravitational attraction. The centripetal force required for the motion of an electron around the nucleus is an electrical force.
Comments (No)