Questions tagged [precession]

The tag has no usage guidance.

66 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
5
votes
0answers
219 views

MRI and precession

A lot of explanations of the quantum mechanics of MRI discuss the precession of a proton in an external magnetic field, for example here: http://www.physicscentral.com/explore/action/mri.cfm Doing ...
4
votes
1answer
1k views

Relation between Zeeman effect and Larmor precession

I'm wondering if there's some intrinsic reason that the precessional frequency, $\omega$, of a spin about an external magnetic field matches the frequency of a photon emitted (or absorbed) in ...
3
votes
0answers
68 views

Precession of a closed orbit under a central force other than the inverse square force

Consider the motion of a closed orbit in a central force field ${\bf F}({\bf r})$ other than the inverse square force i.e., $${\bf F}({\bf r})\neq -\frac{k}{r^2}\hat{\bf r}.$$ However, since ${\bf F}({...
3
votes
0answers
112 views

Stuck on Weinberg's quick derivation of Thomas precession

In Weinberg's Gravitation and Cosmology he has a pretty concise derivation of the Thomas precession formula (Eq. 5.1.13). But I don't get the first step... A particle with intrinsic spin is under the ...
3
votes
0answers
483 views

Start of gyroscopic precession

Let's consider the classical example, the wheel hung by one side of the axle: ¹ When the wheel is not spinning, it will tilt down the free end of the axle first. When the wheel is spinning, it will ...
3
votes
0answers
132 views

How would I explain why a top wobbles to someone who has never taken a physics course?

I found this this website that explains the precession of a top, but obviously, it is not comprehensible to a younger student. I am not referring to why tops stay up, just why they make circles that ...
3
votes
0answers
702 views

3 Axis Gyroscope with forced Precession and Limits of Motion

I am working a problem concerning a 3 axis gryoscope, the spinning mass is a magnet (dipole). This is part of a optical sensing device. The inner gimbal is for pitch rotation, and the outer gimbal is ...
2
votes
3answers
128 views

How do I calculate Earth's axial precession in an idealized Sun-Earth system?

I am experimenting with an idealized two-body system based on the Sun-Earth system. I want to calculate how much Earth's axis precesses and nutates given the simplified setup. In my system, the orbit ...
2
votes
1answer
23 views

Difference in the precession regarding the gravitational gradient

Let say a less massive star acts on a planet causing it to precess.Does a more massive star cause less precession of this planet if in both cases the gravitational force applied to the planet center ...
2
votes
0answers
53 views

How to calculate precision of Pound-Drever-Hall technique?

When I read the fifth section (Noise and fundamental limits: how well can you do?) of Eric's article, I have question. In this section(page 85 and 86), Eric discussed the shot noise, and gave the ...
2
votes
0answers
110 views

Angular velocity in Euler's equations (Rigid body)

I was confused at something... Look at these equations: https://en.wikipedia.org/wiki/Euler%27s_equations_(rigid_body_dynamics) From what I understood the way we get them is by going into rotating ...
2
votes
0answers
177 views

Can there be precession without angular momentum?

In a wikipedia article it is said: The magnetic moment has a close connection with angular momentum called the gyromagnetic effect. This effect is expressed on a macroscopic scale in the ...
2
votes
0answers
53 views

Lense-Thirring Precession of short GRBs

Stone et al. 2014 have proposed that the jet resulting from the merger of a black hole (BH) and neutron star (NS) may precess due to Lense Thirring torques A large rotating mass e.g. the Earth, can ...
2
votes
0answers
137 views

Differential precession due to gravitational waves

To motivate the question, Andy Strominger recently put out a paper on calculating the Sagnac shift of counterrotating beams due to the angular momentum flux of a passing gravitational wave. See here:...
2
votes
0answers
75 views

Precession period matching solar year

Consider the case of a tidally locked planet: its axis of rotation must be perpendicular to the plane of its revolution around the parent star. Therefore, no precession. It is possible for a planets ...
2
votes
0answers
79 views

Does Celestia take the lunar orbit precession into account?

Does the lunar orbit plane rotate (8 year period precession)? Does Celestia take this into account while drawing the moon orbit?
1
vote
0answers
50 views

State of the art on relativistic perihelia precession in Solar System (other than Mercury)

The correct prediction of anomalous precession rate of Mercury perihelion is a classical test of General Relativity and one of its' big triumphs. How about other planets in the Solar System? ...
1
vote
0answers
15 views

What is the relative importance of the Coriolis term to the precession term in frame dragging by rotating Kerr black holes?

The Wikipedia entry for Thirring precession describes the Coriolis term as separate from the precession term. Is it fair to say that when looking at the dynamics of a rotating black hole, the ...
1
vote
0answers
21 views

is room temperature quantum (qubit) nuclear magnetic resonance possible?

I know it is possible to do room temperature NMR. Not just that but one can also use the earth's magnetic field for the nuclei to precess about. If done this way, one gets precession at about the KHz ...
1
vote
0answers
53 views

Precession of a flywheel on earth

I’m currently working on a mechanical problem and I’ve got a couple of questions. First, let me describe the problem. We’ve got a flywheel somewhere on the surface of the earth spinning merrily. It is ...
1
vote
1answer
28 views

How do frame dragging affects a photon for outside observer?

I remember an analogy that explained this phenomenon using magnetic field, a charged particle will experience a force next to another spinning charged particle or something like that. But I don't want ...
1
vote
0answers
74 views

Why stars don't precess?

Assuming that rotation of stars, galaxies etc is determined basically randomly, the question is: why do all space objects rotate so 'neatly', with little or no precession? And what precession there is ...
1
vote
0answers
34 views

Difference between nutation and polar motion

If you add a mass to your spinning globe or just change the mass distribution does it increase nutation or polar motion? And How do I calculate nutation? For this I take earth as an example. from what ...
1
vote
2answers
106 views

Do protons and electrons actually precess?

I know that protons and electrons do not actually spin, although they have the property of spin. I was learning about MRI. I was introduced to the idea that you have the spin of the proton in the ...
1
vote
0answers
48 views

Why is precession angular velocity constant?

I am currently studying precession, and have a question regarding the angular velocity of precession. Let's simply use a spinning top in this case. I understand that it is given by the formula $$ \...
1
vote
1answer
239 views

Precession of Angular momentum of Symmetric Top

For a torque free symmetric top, is the angular momentum in body fixed coordinates in same direction as instantaneous axis of rotation? I know that instantaneous axis of rotation precesses about ...
1
vote
1answer
203 views

How much force is required to break precession?

Gravity, in this diagram, provides a downward force creating a torque that causes the wheel to precess around the chain. This is cool but counter intuitive, and I am wondering what force is needed to ...
1
vote
0answers
57 views

Does the angular velocity of a wheel affect its height in this situation?

If there were no friction at all, and the wheel was spinning with some angular velocity in the initial picture shown below. Would the wheel stay perpendicular to the ground regardless of the angular ...
1
vote
0answers
38 views

How can magnetic dipole align if there is precession?

In my lecture notes on paramagnetism and diamagnetism is stated that "according to van vleck critical considering an electron in motion around the nucleus diamagnetic and paramagnetic effect ...
1
vote
2answers
240 views

Gyroscope precession and Euler equations

I've been trying for so long to solve this problem, but the solution I have found isn't the one I expected. Basically, I have to solve Euler's equations for a gyroscope with a weigth at a distance d. ...
1
vote
1answer
53 views

Can we measure the angular momentum of a magnetic domain using precession?

The amount of angular momentum of a single iron atom is small, just $\hbar / 2$. In a single magnetic domain, though, all of the iron atoms have their spins aligned. Presumably, it should be possible ...
1
vote
1answer
213 views

Does asymmetric rigid body experience torque-free precession?

I know that a top (or any axis symmetric body) experience torque-free precession. and I know that asymmetric body, with 3 different dimensions has stable rotation when the angular velocity is near the ...
1
vote
1answer
375 views

Nutation frequency for a weighted gyroscope

So, I've been led to believe that the frequency of nutation of a gyroscope can be calculated using the formula In which the I's are the moments of inertia around the principal axes and omega-3 is the ...
1
vote
0answers
113 views

Planar Precession Frequency of Orbit

What is the general relation between orbital precession $\Phi$, orbital frequency $\Omega$ and a radial perturbation frequency $\omega$? For certain cases the answer is "clear", for example: 1) If $\...
1
vote
0answers
336 views

Where did Paul Gerber go wrong in arriving at the same equation as Einstein in explaining the Mercury anomaly?

We know that Einstein admitted that Paul Gerber's 1898 formula explaining the anomaly of Mercury's perihelion was the same as his own. Reportedly Gerber had made a mistake somewhere, so - even though ...
1
vote
1answer
66 views

Does Earth's precession rate change with the seasons?

As Earth's precession is caused by the differential solar, etc., attraction to its 'spare tire', then does the rate go to ~zero at the equinoxes and ~twice the average at the solstices? (preferred ...
1
vote
0answers
176 views

How is the precession rate of planets calculated? For which planets do we know the precession rates?

From what I've read, precession rates of Earth, Mars and Moon are known. Why is that? And how is it calculated?
1
vote
2answers
629 views

How does precession affect angular momentum?

I have been studying Irodov's problem book. There are a lot of good problems that challenge conceptual knowledge, and so I have to ask somebody for a qualitative answer. I can best describe my ...
1
vote
0answers
159 views

Motor-powered gyroscope's precession speed

I was doing experiment about the gyroscope's precession speed and I made my own gyroscope, which is the one in the picture. It is the motor-powered gyroscope as I found out the one made with bearing ...
1
vote
0answers
1k views

Precession of Mercury (Python simulation)

I was trying to simulate the precession of Mercury based on the perturbed solution, and my questions about its implementation in python can be seen here: https://scicomp.stackexchange.com/questions/...
1
vote
0answers
81 views

Larmor Precession of a macroscopic number of electrons

I know that there are some similiar questions out there, but I'm still quite puzzled by the following problem. Say i have a box full of interacting electrons ( I'm not sure if it would change anything ...
1
vote
0answers
1k views

Direction change of gyroscopic precession with change in moment of inertia

In the classic bicycle wheel gyroscopic precession, using the right hand coordinate system of xyz and right hand rule of rotation, Such as X axis is in the longitudinal direction (spin axis) z axis ...
1
vote
1answer
613 views

Why do nuclei precess in magnetic fields?

I understand that a classical bar magnet will precess about the axis of an external magnetic field. Whilst researching NMR, I have read that nuclei with half-integer spin which are subject to an ...
0
votes
0answers
14 views

Is electron diamagnetic resonance (invoking Larmor precession) possible?

Diamagnetism is observed in materials where electrons are paired. These paired electrons have opposite magnetic dipole moments. Therefore, the total magnetic torque on the pair's magnetic dipole ...
0
votes
0answers
14 views

How much differs the Mercury speed at perihel from its theoretical speed with no frame dragging involved?

How much differs the Mercury speed at perihel from its theoretical speed with no frame dragging involved? Can a formula of frame dragging velocity be calculated regarding the distance of a point of ...
0
votes
1answer
24 views

Does precession affect loss of angular velocity in collisions?

I'm a higher schooler trying to do a project on how moment of inertia affects loss of angular velocity in spinning top collisions. Right now, I'm trying to find factors that might affect my results ...
0
votes
1answer
47 views

What is the Precession direction of positron?

In Larmor precession; The spin angular momentum of an electron precesses counter-clockwise about the direction of the magnetic field(An electron has a negative charge, so the direction of its magnetic ...
0
votes
0answers
18 views

Do paired electrons precess under a magnetic field? Is there a way to know?

The spins of paired electrons are opposite of one another, but so are their magnetic moments. Thus, an externally applied magnetic field will exert opposite torques to opposite spins. Doesn't that ...
0
votes
1answer
42 views

Is precession a property of asymetric objects only? How to explain Larmor precession?

Is precession a property of asymmetric objects only? How to explain Larmor precession? A proton could be asymmetric due to its compositeness but what about electrons?
0
votes
0answers
32 views

Gyroscopic Torque

I was going through this problem in which there was a disc mounted at one end of the rod and the other end of the rod is hanged using a rope. The disc is given angular velocity counter-clockwise. Now ...