Differences between Centrifugal Force and Centripetal Force
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Centrifugal Force vs. Centripetal Force[edit]
In the context of circular motion, centripetal and centrifugal forces are often discussed. Centripetal force is a real force that causes an object to follow a curved path, whereas centrifugal force is an apparent outward force experienced by an object moving in a rotating frame of reference.[1][2] A key distinction lies in the frame of reference: centripetal force is observed from an inertial (non-accelerating) frame, while centrifugal force is apparent in a non-inertial (accelerating or rotating) frame.[3][4]
Centripetal force always acts inward, toward the center of the circular path.[5] This force is what constrains an object to move in a circle; without it, the object would continue in a straight line due to inertia. Different physical interactions can provide the centripetal force. For planets orbiting the sun, gravity is the centripetal force.[1] For a car turning a corner, the friction between the tires and the road provides the centripetal force.[3]
In contrast, centrifugal force is considered a fictitious or pseudo-force because it does not arise from any physical interaction with another object. It is an effect of inertia. An observer in a rotating frame of reference, such as a person on a merry-go-round, feels a push outward. This perceived outward force is the centrifugal force.[1] From an inertial frame of reference, there is no outward force acting on the person; the inward-acting centripetal force provided by the structure of the ride is the only real force causing the circular motion.[1]
Comparison Table[edit]
| Category | Centripetal Force | Centrifugal Force |
|---|---|---|
| Definition | The force that compels an object to follow a curved path, directed towards the center of curvature.[3] | An apparent outward force on a rotating object, viewed from within the rotating frame of reference. |
| Nature of Force | A real force resulting from physical interactions (e.g., gravity, tension, friction). | A fictitious or inertial force that arises from the acceleration of the reference frame, not from an interaction. |
| Direction | Inward, toward the center of the circular path. | Outward, away from the center of rotation.[3] |
| Frame of Reference | Observed in an inertial (non-accelerating) frame of reference.[3] | Experienced in a non-inertial (rotating or accelerating) frame of reference. |
| Origin | Caused by fundamental forces such as gravity, tension, or friction. | An effect of an object's inertia in a rotating frame. |
| Effect | Causes a change in the direction of the object's velocity, resulting in circular motion. | Pushes an object away from the center in a rotating frame; it is the reaction to the centripetal force. |
Inertial and Non-Inertial Frames of Reference[edit]
The distinction between these two forces is dependent on the observer's frame of reference. An inertial frame is one that is not accelerating.[4] In such a frame, Newton's laws of motion hold true without the need for fictitious forces. When observing an object moving in a circle from an inertial frame, the only horizontal force acting on it is the inward centripetal force.[1]
A non-inertial frame is one that is accelerating.[4] A rotating frame of reference is a common example of a non-inertial frame. To apply Newton's laws within a non-inertial frame, fictitious forces like the centrifugal force must be introduced to account for the frame's acceleration. For an observer in a rotating car, the sensation of being pushed outward is explained by the centrifugal force, which balances the inward centripetal force, making the observer feel stationary relative to the car.
References[edit]
- ↑ 1.0 1.1 1.2 1.3 1.4 "livescience.com". Retrieved October 17, 2025.
- ↑ "patsnap.com". Retrieved October 17, 2025.
- ↑ 3.0 3.1 3.2 3.3 3.4 "byjus.com". Retrieved October 17, 2025.
- ↑ 4.0 4.1 4.2 "geeksforgeeks.org". Retrieved October 17, 2025.
- ↑ "merriam-webster.com". Retrieved October 17, 2025.
