# Centrifugal Definition and 27 Discussions

In Newtonian mechanics, the centrifugal force is an inertial force (also called a "fictitious" or "pseudo" force) that appears to act on all objects when viewed in a rotating frame of reference. It is directed away from an axis which is parallel to the axis of rotation and passing through the coordinate system's origin. If the axis of rotation passes through the coordinate system's origin, the centrifugal force is directed radially outwards from that axis. The magnitude of centrifugal force F on an object of mass m at the distance r from the origin of a frame of reference rotating with angular velocity ω is:

The concept of centrifugal force can be applied in rotating devices, such as centrifuges, centrifugal pumps, centrifugal governors, and centrifugal clutches, and in centrifugal railways, planetary orbits and banked curves, when they are analyzed in a rotating coordinate system.
Confusingly, the term has sometimes also been used for the reactive centrifugal force, a real inertial-frame-independent Newtonian force that exists as a reaction to a centripetal force.

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1. ### Number of Decks on a Rotating Habitat

My current spaceship design with several ring habitats (6 in my case) works well for worldbuilding purposes, in the sense that the reader should easily be able to tell what types of facilities can be found where on the ship. That’s because the rings distinguish themselves from each other by...
2. ### I Physics behind making a mango milk shake

Hi Folks!I have limited understanding of physics. I am trying to put into words the working principles of a mixer grinder, specifically for making a mango milkshake. So far, these are the steps I have come up with: Where am I wrong? What things have I gotten right? Thanks!
3. ### A Mass dropped onto rotating disk

Picture a flat disk of radius r with a radial vane. The disk is rotating at angular velocity w. Assume the vane is straight, starts at the center and ends at the perimeter of the disk. A very small round mass ( of m grams) is dropped onto the disk very near the center. The vane contacts it and...
4. ### How does Newton's 1st Law impact centrifugal force? Does it exist?

The reading that I have says that centrifugal force (center fleeing) does not exist
5. ### B Confusion while trying to build intuition of centripetal force

As I understand it, when a body undergoes uniform circular motion its velocity does not change in magnitude but instead direction. This change in velocity, or acceleration, is directed inward towards the center of the circle. If a body was not experiencing a net centripetal acceleration, then...
6. ### Does Water Swirl the Other Way in the Southern Hemisphere?

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7. ### Matt & Hugh play with a Brick and derive Centripetal Acceleration

Matt and Hugh play with a tennis ball and a brick. Then they do some working out to derive the formula for the centripetal force (a = v^2/r) by differentiati...
8. ### Calculating frictional torque

Homework Statement Hello, so I currently designing a centrifugal brake, I know how much torque it needs to stop etc just unsure of a few things. How would I calculate frictional torque? I understand that I can use the net torque to determine what torque is needed for equilibrium etc however I...
9. ### I Fictitious forces -- name convention

Hello all, I understand there are four d'Alembert (fictitious) (non-inertial) forces: 1. Coriolis 2. Centrifugal 3. Linear 4. Angular acceleration. But then I think about the Gyroscopic Effect (I understand how it arises, so that is not the issue). I am wondering if one can "classify" these...
10. ### I What is the tangential component? Taylor p.347

I do not understand why the tan component for a gravity affected by the centrifugal force: g = Ω^2 * R * sinθ * cosθ So I tried to draw this: using a "big" X-shaped axis where the / component goes along the main gravity direction while \ points normal to / this direction. Then the centrifugal...
11. ### Centrifugal propulsion

Hi I am spending time on youtube looking at videos that come up when I search "Centrifugal propulsion" (No need for me to pick a few, you can do a search and see lots.) Most of the videos look poorly made. All show some sort of "vehicle." But the "vehicle" jitters back and forth. I am...
12. ### Shape of water in a rotating container along A vertical axis

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13. ### I Caculate the reaction force of a radially moving object

Hello, An object moves outward in shaft radially due to centrifugal force. lest say it weights 1kg . in a timestep=0.0001 it travels 0.0017 meters this is actually the difference of two radius, let say first radius r1 = 0.25 meters second r2 = 0.25 + 0.0017 meters rpm of the rotating system...
14. ### Using a centrifuge to extract heavy water (help with the calculations please)

Hello everyone! I have seen several DIY projects which successfully gathered heavy water from normal water. For example Cody from codys lab used electrolysis to "enrich" the water. This however is a messy process. So i became curious, if this can be done easier by centrifugation. Based on...
15. ### Questions about understanding circular motion & the forces involved

Hey, I'm having some difficulty in understanding circular motion and it's forces. Here is the situation I'm on: Imagine you are on a smooth turn-table with smooth shoes and the table starts spinning. Because of inertia, and because the frictional force is not nearly enough to keep you going in a...
16. ### Centrifugal term in mechanical energy in gravitation

I'm studying effective potential in Newtonian gravitation. The mechanical energy of a body can be written $$E=\frac{1}{2}\mu {\dot{r}}^2+\frac{L^2}{2\mu r^2}-\gamma \frac{m M}{r^2} \tag{1}$$ Where \mu is the reduced mass of the system planet-star. Consider now the term...
17. ### Feynman & Tidal Forces

I used to think I understood this - big mistake! I've just watched a great classic Feynman lecture posted by another PF user (a superb way to spend 50 mins of you can spare the time) https://www.physicsforums.com/threads/i-found-the-best-teacher-of-physics.855335/ In that lecture, Feynman...
18. ### B Maximum Radius for Wall of Death

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19. ### Centripetal/Centrifugal Motion on a merry-go-round

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20. ### Use centrifugal pump as air pump?

I need to deliver air up to 5 meters high. I am thinking of using pump since I can find easily (no buying anything). Is it possible to deliver air using hydraulic centrifugal pump ?
21. ### Centripetal combined with Gravitational Force

Hi! So I learned Newtons Law of Gravity and used the numbers to calculate that the acceleration due to the attraction between masses is 9.8m/s/s. Hooray! This is what I've learned is the acceleration due to gravity. However, does the rotation of the Earth and the subsequent centrifugal force...
22. ### Centrifugal Spaceship Accelerator

Suppose we launch two ships and move them close to the Sun. They have solar collectors and can absorb a massive amount of energy thanks to their proximity to the Sun. The ships are connected by a 1000 meter long rod of titanium, and each ship's rocket is position opposite the other's, so that...
23. ### Car going around loop

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24. ### Vibration/Centrifugal Force Question

Hello I am making a vibration project which requires me to mount eccentric weights on both sides of an electric motor. I must submit the "generated force(in Kg)" by this motor. The RPM of motor = 1000 Total weight on both sides of the motor = 16.8Kg (8.4Kg on both sides) The radius(distance...
25. ### Maximum angular velocity for a Neutron Star: Textbook - Physics for Scientists and Engineers

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26. ### Mechanical forces

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27. ### Confusion with the centrifugal foce and potential energy

When we release a suspended object, we recover the potential energy due to gravity as the object travels back through the height raised. When we release an extended spring, we recover the potential energy as the object travels back through the distance stretched. But when we release a rotating...