What Is Centripetal Force?
According to Newton’s first law of motion, a moving body travels along a straight path with constant speed (i.e., has constant velocity) unless it is acted on by an outside force. For circular motion to occur there must be a constant force acting on a body, pushing it toward the center of the circular path. This force is the centripetal force. Thus, centripetal force can simply be described as a force that causes an object to move in circular motion.
The magnitude F of the centripetal force is equal to the mass m of the body times its velocity squared v ^{2} divided by the radius r of its path: F=mv^{2}/r.
Examples of Centripetal Force
- The moon or a manmade satellite orbiting the Earth
- If an object was being swung around on a rope the centripetal force is the tension in the rope.
- Planets revolving around the Sun
- A loop traveled on by a roller coaster is another example of centripetal force.
- Centripetal is the force that prevents the moon from floating out of the Earth’s orbit.
What Is Centrifugal Force?
Centrifugal force is a force that tries to push a body away from the circular motion. Centrifugal results from inertia, the tendency of an object to resist any change in its state of motion or when it is at rest, though it does not exist when a system is described relative to an inertial frame of reference.
The centripetal force is always directed perpendicular to the direction of the object’s displacement. Using Newton’s second law of motion, it is found that the centripetal force of an object moving in a circular path always acts towards the centre of the circle. Often times it is called an “apparent force”, mainly because it feels like a force.
The Centripetal Force Formula is given as the product of mass (in kg) and tangential velocity (in meters per second) squared, divided by the radius (in meters). Which implies that on doubling the tangential velocity, the centripetal force will be quadrupled. Mathematically it is written as: Fc=mv^{2}/r. Where, F is the Centripetal force, m is the mass of the object, v is the speed or velocity of the object and r is the radius.
Examples of Centrifugal force
- The mud flying off of a spinning tire
- Children being pushed out on a merry-go-round. The force the children feel is centrifugal force pushing them outward.
- A car skidding off the surface while taking a turn.
Also Read: Difference Between Mass And Weight
Difference Between Centripetal And Centrifugal Force In Tabular Form
BASIS OF COMPARISON | CENTRIPETAL FORCE | CENTRIFUGAL FORCE |
Description | Centripetal force refers to a force that causes a body to move in circular motion. | Centrifugal force is a force that tries to push a body away from the circular motion. |
Discovery | Centripetal force was first described by Isaac Newton in 1684. | Centrifugal force was first described in 1659 by Christiaan Hygens. |
Nature | At every instant, it is directed radially towards the center of the circular path. | At every instant, it is directed radially away from the center of the circular path. |
Action | It is a real force arising from gravitational or electromagnetic interaction between matter. | It is a pseudo force since it is the effect of the acceleration of the reference frame of the revolving particle. |
Causes | Centripetal force can be caused due to factors like tension, gravitational pull, electrostatic force etc. | The inertia of an object causes the centripetal force. |
Examples | Planets revolving around the Sun or a satellite orbiting a planet. | Mud flying off a tire or a Car skidding off the surface while taking a turn. |
Effect | The centripetal force causes us to enter into a circular motion. | The centrifugal force causes us to come out of a turn or a out of a circular motion. |
Formula | Fc=mv^{2}/r | Fc=mv^{2}/r |
What You Need To Know About Centripetal And Centrifugal Force
- Centrifugal force was defined in 1659 by Christiaan Hygens, and Isaac Newton defined centripetal force 25 years later in 1684.
- If an object is moving in a circle and it experiences an outward force then this force is referred to as centrifugal force.
- If the object travels in a uniform speed in a circular path then the force acting on the object is referred to as centripetal force.
- The centripetal force on an object depends on an object’s tangential speed, its mass and the radius of its circular path.
- Generally, centrifugal force is considered to be an equal and opposite reaction to the centripetal force.
- Centrifugal force takes place along the radius of the circle from the center out towards the object. For centripetal it is the opposite, taking place also along the radius of the circle, but from the object in towards the center.
- Centrifugal force is more of an apparent force and is not a real force, though it is directly related to centripetal force, which is a real force.
- Centrifugal results from inertia, the tendency of an object to resist any change in its state of motion or when it is at rest.
- The formula for centrifugal and centripetal force is the same: F = mac = mv^{2}/r. ac is the centripetal acceleration; m is the mass of the object, moving at velocity (v) along a path with radius of curvature (r).
Conclusion
Centripetal force and Centrifugal force, action-reaction force pair associated with circular motion. The centripetal force, the action, is balanced by a reaction force, the centrifugal force. The two forces are equal in magnitude and opposite in direction. The centrifugal force does not act on the body in motion; the only force acting on the body in motion is the centripetal force. The centrifugal force acts on the source of the centripetal force to displace it radially from the center of the path.
The magnitude F of the centripetal force is equal to the mass m of the body times its velocity squared v ^{2} divided by the radius r of its path: F=mv^{2}/r.
The centrifugal force is often mistakenly thought to cause a body to fly out of its circular path when it is released; rather, it is the removal of the centripetal force that allows the body to travel in a straight line as required by Newton’s first law (a moving body travels along a straight path with constant speed (i.e., has constant velocity) unless it is acted on by an outside force).