Centrifugal Force

The phenomenon of centrifugal force is a concept of physics. This concept has been framed to explain the force which is created when an object is in rotation, as well as to elucidate, what keeps an object, when set in a rotational motion, moving in circles for sometime before coming to a standstill. The term centrifugal has been coined by combining two distinct Latin words - centrum (meaning center and fugere (meaning to escape) - together. Therefore, centrifugal force can be roughly defined as a force which escapes from the center of a rotating body in an outward direction while the object is in circular motion. In turn, this outward force keeps the object moving in a circular motion for sometime before it becomes stationary again. Let's take a more detailed look at centrifugal force and its mechanics.

What is Centrifugal Force?

As mentioned above, centrifugal force is that force which is created when an object is in rotation and this force spreads in an outward direction, causing the central point or axis (imaginary central part) of the object to experience an inertia-like state. To quote the definition as given by Wikipedia, centrifugal force represents the effects of inertia that arise in connection with rotation and which are experienced as an outward force away from the center of rotation. A very good example of the centrifugal force in action is the hammer throw item in athletics events. As the athlete starts to swing the heavy hammer in circular motion, the centrifugal force coming from the center of this circle of velocity, that is from the body of the athlete towards the head of the hammer, causes the motion of the hammer to gain momentum and when released, this momentum is responsible for making the hammer land far away from the athlete when it is released by him, while still in motion.

Two Concepts of Centrifugal Force

There are two distinct concepts of centrifugal force - fictitious centrifugal force and reactive centrifugal force. Fictitious centrifugal force defines the force that is produced during the phenomenon of a circular motion which takes place in a non-inertial reference frame. For instance, the outward force that emanates from the core due to rotation of planets on their own axes is a case of fictitious centrifugal force. On the other hand, reactive centrifugal force is a force that is result of the centripetal force that occurs when an object is moving along a curved path. While accelerating towards the mean location of the curve, an object also, invariably, accelerates towards its own mean location or axis. A good example would be a ball that is rolling along a curved path. While moving towards the curve, the ball is also undergoing rotation on its imaginary axis. The revolution of planets around the sun while continuing to rotate on their respective axes is another good example of reactive centrifugal force.

Calculation

Centrifugal force can be calculated by the using the following equation as a formula:-

F_cf = +mv² / r = +mrw²

where:

• F_cf = centrifugal force
• m = mass of the object that is in rotation
• v = linear velocity of the rotating object
• r = radius of the curvature
• w = angular velocity of the moving object

Another question that arises with reference to centrifugal force is about relative centrifugal force. Well, relative centrifugal force is simply a multiplier for the force of gravity during rotation. It may be expressed as a value of the strength or number of times the force of gravity with relation to centrifugal force that acts on the object in question.

That was a brief overview of what centrifugal force implies and how it can be calculated in terms of mathematics to derive a numeric value for purpose of measurement and comparison. This concept is often confused with centripetal force. While the former describes the force of motion that emanates from within the object's core in an outward direction, the latter describes the force that is created (and which propels the object along) when an object is moving along a curved pathway. Hope that helps!