Questions tagged [centrifugal-force]
Centrifugal force is an inertial (pseudo or fictious) force used in a non-inertial frame of reference in order to apply the Newton's laws of motion. If your question is about centripetal force, which is a real force that points towards the center of a circular trajectory, use the tag "centripetal-force" instead.
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Is Earth really flattened at the poles because of centrifugal force?
My question is pretty much all in the title. I was always told that our planet is flattened at its poles due to the centrifugal force generated by its own rotation. However I don’t see how centrifugal ...
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Apparent weight of body due to rotation of earth [duplicate]
This question has been asked several times on this site. However, most of the answers were
qualitative in nature.
Suppose a body is placed at a point on earth's surface at latitude $\theta$ from the ...
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How can you derive the formula for the apparent weight at any latitude on the Earth?
My textbook derives the formula for apparent weight at the equator, which is just equating the centripetal force to the difference between the true weight and normal reaction.
$$ mg' = mg + m \omega^2 ...
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Why does a centrifuge cause blood to be pushed downwards in the human body?
Good evening all,
I recently watched this YouTube video about a centrifuge by Tom Scott
(https://www.youtube.com/watch?v=DMKcO-T5Y4o). Around the 2:30 mark, it is said that blood will be 'pushed ...
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Forces on someone flying off a carousel
Good afternoon all,
I'm trying to model a physics problem and would greatly appreciate some help.
The situation that I'm looking at involves a person on a carousel, and the angular velocity required ...
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Why is centripetal force acting 'away' from centre in this situation?
In this problem, a guy is moving along this circular track at constant speed.
When he is at B, the centre of motion is 'downwards', isn't it?
So there must be centripetal force on the cyclist that is ...
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Is rotation artificial gravity like a "O'Neill cylinder" anything like keeping smoke in a bucket with centrifugal force in deep space or a vacuum?
(O'Neill cylinder) the force that would keep smoke in a bucket.The force of keeping smoke in a rotation bucket in a vacuum.Is it the weight of the smoke?
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Is the centre of rotation in non-inertial rotating frame different from the actual centre? (Is my animation correct)
(Sorry for confusing question, here's the actual explanation)
If Im sitting on the edge of a rotating merry-go-round, then from my perspective the world is rotating around me. Now, there is a fixed ...
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Why does water in spinning bucket move out outward if centripetal and centrifugal forces cancel out?
Evey source I saw keeps saying change in shape of water is due to centrifugal force but it cancels out with centripetal force
And if you see from inertial frame of reference the water shouldn't moving ...
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Is it possible to split up air into its parts by something like centrifuging? [duplicate]
Is it possible to centrifuge cases to split them up into their compounds (at least temporarily)?
For instance, the air is composed of 78% nitrogen, 21% oxygen, 0.9% argon, and other gases. Under what ...
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If I have a washing machine with feet not attached at all to the floor, will it begin to walk on a opposite angular velocity?
The title is self-explanatory, but I will give some more details.
So, let's suppose the washing machine can move, that is, it doesn't have any protections for not moving. Let's also suppose it's ...
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Magnitude of centrifugal force [closed]
A pendulum is designed for use on a gravity-free spacecraft. The pendulum consists of a mass at the end of a rod of length $l$. The pivot at the other end of the rod is forced to move in a circle of ...
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Centrifugal force in an open system
Do you need to be in contact with a surface for centrifugal force to apply in an open structure?
E.g. if a bird flew into a fairground ride that uses centrifugal force to pin people to a wall, would ...
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How are quadratic terms of apparent force in a rotating reference frame derived from the usual decomposition into centrifugal and Coriolis terms?
Usually the total acceleration a' seen in a rotating reference frame (like earth) is written down as
$$\vec a' = -\vec \omega \times \left(\vec \omega \times \vec r' \right) - 2 \cdot \vec \omega \...
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"Centrifugal Force" felt in a turning car
From my understanding, when you are in a turning car, assuming that you are not touching any part of the car except the seat, the frictional force from the seat is acting as the centripetal force. Is ...
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What real force causes outward acceleration in rotation?
Consider a thick solid cylinder with a smooth groove along a diameter. If a block was placed somewhere in the groove and the cylinder was spun about an axis passing through its centre, I think the ...
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Why the body don't fall down in Loop-the-Loop Situation?
In Ramamurti Shankar playlist fundamentals of physics
he talked about Loop-the-Loop example which is if a trolley in a roller coaster and it's at the top of it why the roller coaster didn't fall down
...
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Newton-Euler formulation
How to find the translational and rotational equations of motion when the center of gravity does not coincide with the origin of the fixed-body rotating frame?
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At which colatitude $\theta$ is the error between $\vec g_{eff}$ and $\vec g$ maximum? [closed]
Suppose a plumb bob hangs without swinging, then the string defines the
effective direction of gravity. Suppose you are holding the bob on the surface of the
earth at colatitude $\theta$, where $\...
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Does the Coriolis force apply to an object moving weightlessly in a tunnel around the center of Earth?
I just want to be sure I understand correctly.
They ask us to find the speed at which an object moves weightlessly in a tunnel around the center of the Earth. Assume Earth is homogeneous, and the part ...
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Would externally applied centrifuge force push electron out of an atom?
Background about me: I know nothing about physics.
It occurred to me to ask the following question:
Imagine a small amount of some element placed in centrifuge device that spins with very fast speed. ...
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Potential at a point on Earth due to orbital motion and the Moon
In "Physics of the Earth" by Frank Stacey and Paul Davis, they approximate the height of the tides on page 103.
They assume the Earth is perfectly spherical, covered in a uniform layer of ...
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Substituting the conservation of angular momentum into the Binet formula results in contradiction [duplicate]
Background Information
The lagrangian of a particle in a central force field $V(r)$ is
$$
L=\frac12m(\dot r^2+r^2\dot\theta^2+r^2\sin^2\theta\dot\varphi^2)-V(r).
$$
The particle must move in a plane, ...
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Does gravity cause the Earth's equatorial bulge?
The way I understand centrifugal force, I don't see how Earth's daily rotation alone would cause equatorial bulges to form. The usual explanation is that the centrifugal force increases with distance ...
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If one "fell" from the center of a spinning space station, which was creating "gravity" by using centripetal force, what forces would one feel?
Let's imagine a grand hamster wheel in space. The wheel is very large and is constructed of the same reasonably inelastic material. It has three main features: The first is a solid disk rotating at ...
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What force accounts for Earth's equatorial bulge in an inertial frame of reference?
I am confused as to how Earth's centrifugal effects from its daily spin can be explained from an inertial frame of reference relative to the distant stars. The usual explanation is that the ...
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Can you fall in a Gravitron centrifuge ride?
I went on a Gravitron ride with my 5 year old son. He became "hysterical" with fear and started pushing himself off the wall.
I my arm across his body trying to keep/push him back as he was ...
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Why aren't fusion reactors using centrifuges?
If fusing of nuclei in stars requires pressure, heat, and gravity, why not use a centrifuge to increase the gravity? We currently have the technology to make diamonds, and generate immense ...
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Gravitational Potential of a Slowly Spinning Planet
I'm working on a problem in Thorne & Blandford's Modern Classical Physics regarding the shape of a constant density, spinning planet (Exercise 13.5). It asks you to argue that the gravitational ...
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Alternative formula for centrifugal force
The centrifugal force has the formula
$$ f_C=\Omega^2r $$ and vectored
$$ \vec{f_C}=\vec{\Omega} \times(\vec{\Omega}\times \vec{r}) $$
However there is also the known formula
$$ f_C=\frac{v^2}{r} $$
...
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Clarification on centrifugal force in non-inertial reference frames
Background:
Let’s say we have a trajectory $\vec{y}(t)$ expressed in coordinates of an accelerated reference frame. In an inertial reference frame the trajectory is given by: $\vec{x}(t)=R(t)\vec{y}(t)...
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Why is it said that gravity is weaker at the equator due to centrifugal force? [duplicate]
Gravity would only be weaker at the equator if mass is not the only thing that produces gravity or if there is dense enough matter near, or at, the center to offset the additional volume of mass that ...
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Apparent weight due to the rotation of earth
My concern here is that, if you were to calculate the apparent weight of an object due to earth's rotation at the equator, most text books use centripetal force and it works totally fine, but when it ...
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Could centrifugal force save this scene in movie "Gravity"?
The scene on movie "Gravity" where George Clooney dies has taken a lot of heat, and I could not find one single person able to defend it, as physics is concerned. There is even an interview ...
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In a centrifugal separator how does the heavy or light phase move upwards?
I've been studying about the working principles of a centrifugal separator. Even though i understand how centrifugal force separates the liquid into 2 phases(heavy and light) i cant make sense of how ...
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End motion of an empty spherical shell with a ball rolling on it's inner surface
Let's picture an empty sperical shell in inter galactic space or beyond. Inside this shell, a ball is rolling on the inner surface. Because of friction and the centrifugal force the ball exerts on the ...
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What is the action pair of normal reaction in case of bike riding along a curved vertical wall
I was reading about a situation in my brother’s physics textbook where a bike is riding along a curved vertical surface. It’s mentioned there that normal reaction provides the centripetal force and ...
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A simple proof that under Newtonian gravity rotating massive bodies are ellipsoids?
Here is my attempt at deriving the shape of an idealized rotating massive body under Newtonian gravity, assuming that the gravity force points towards the center of mass and shape of the body is ...
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Does the Lagrange Point $L_3$ exist in practice in the multi-body solar system?
Lagrange Points ($L_1$ through $L_5$) in a restricted 3-body system are well documented. Traditionally body 1 (M1) is the central object with a mass much greater than the other two objects. M2 is ...
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What would happen if the Earth rotated at the rate required to achieve orbit at its radius? I.e ~7k m/s instead of ~460 m/s
To achieve a circular orbit, you need to have a velocity of $$v = \sqrt{Gm/r}$$ which is about 7 km/s at the Earth’s radius, but the Earth’s rotational speed is only about 460 m/s (by taking the ...
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Could we measure fictitious forces arising from rotation about an axis in a fourth spatial dimension?
Two-dimensional creatures confined to a flat sheet that was uniformly rotating around an axis perpendicular to the sheet would have no trouble identifying that their sheet was rotating. They would be ...
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Centripetal acceleration in rotational and translational motion
How do you find the centripetal acceleration of any point on a body performing both rotational and translational motion.
For example, in pure rolling if we find centripetal acceleration of the topmost ...
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What is the name of the instrument that separates substances using an electromagnetic field, similar to spectrography
As far as I remember, the elements of the substance are passed across an electromagnetic field in such a way that they seperate as the electromagnetic field alters their trajectory. I also seem to ...
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Heavy mass vs light mass in circular motion
If I have 2 spheres with different mass in a spinning Y shaped tube(no water is in the tube),
which one will go higher because of inertia ...
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Angular momentum in a centrifuge
Just a curiosity, centrifuges are ideally perfectly balanced, but can tolerate some level of imbalance. Is this due to the angular momentum of the rotor residing rapid oscillations in tilt? How would ...
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Central force problem: the basics
In a central force problem, let $r'$ mean the derivative of the radial distance with respect to time, then
(m$r''$ - mr$\theta''^2$ )($\vec{r}$) = f($\vec{r}$) , the radial force.
Please check if ...
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Gravitational force, centrifuge?
So after going through 5 pages on google on why and how a centrifuge separates out particles of different densities, I still don't quite get this.
If Galileos statement is right that force can be ...
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How to understand what causes the centripetal force in this situation and what would be the direction of those forces and the centripetal acceleration [closed]
A table with smooth horizontal surface is turning at an angular speed $ω$ about its axis. A groove is made on the surface along the radius and a particle is gently placed at a distance $a$ from the ...
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How large are the fictitious forces due to our orbit around the galactic center?
When we are in a non-intertial system, this creates fictitious forces. Some well-known fictitious forces are the centrifugal and coriolis forces. Those are caused by the Earth's spin around its axis.
...
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On a Torus World and the force upon inhabitants
I am looking into torus worlds for fiction, and I know how to calculate the necessary speed to rotate, and necessary radius, for such a world to get a specific force of gravity.
But what I am ...
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