what is centripetal and centrifugal force
Answers
Centrifugal force is ubiquitous in our daily lives. We experience it when we round a corner in a car or when an airplane banks into a turn. We see it in the spin cycle of a washing machine or when children ride on a merry-go-round. One day it may even provide artificial gravity for space ships and space stations.
Some people confuse centrifugal force with its counterpart, centripetal force, because they are so closely related. One might say they are two sides of the same coin. Centripetal force is defined as, “The component of force acting on a body in curvilinear motion that is directed toward the center of curvature or axis of rotation,” while centrifugal force is defined as, “The apparent force, equal and opposite to the centripetal force, drawing a rotating body away from the center of rotation, caused by the inertia of the body,” according to the American Heritage Dictionary.
Note that while centripetal force is an actual force, centrifugal force is defined as an apparent force. In other words, when twirling a mass on a string, the string exerts an inward centripetal force on the mass, while mass appears to exert an outward force on the string.
“The difference between centripetal and centrifugal force has to do with different ‘frames of reference,’ that is, different viewpoints from which you measure something,” according to Andrew A. Ganse, a research physicist at the University of Washington. If you are observing a rotating system from the outside, you see an inward centripetal force acting to constrain the rotating body to a circular path. However, if you are part of the rotating system, you experience an apparent centrifugal force pushing you away from the center of the circle, even though what you are actually feeling is the inward centripetal force that is keeping you from literally going off on a tangent.
This apparent outward force is described by Newton’s Laws of Motion. Newton’s First Law states that “A body at rest will remain at rest, and a body in motion will remain in motion unless it is acted upon by an external force.” If a massive body is moving through space in a straight line, its inertia will cause it to continue in a straight line unless an outside force causes it to speed up, slow down or change direction. In order for it to follow a circular path without changing speed, a continuous centripetal force must be continuously applied at a right angle to its path. The radius r of this circle is equal to the mass m times the square of the velocity v divided by the centripetal force F, or r = mv2/F. The force can be calculated by simply rearranging the equation, F= mv2/r.
Centrifugal force is ubiquitous in our daily lives. We experience it when we round a corner in a car or when an airplane banks into a turn. We see it in the spin cycle of a washing machine or when children ride on a merry-go-round. One day it may even provide artificial gravity for space ships and space stations.