As of May 31, 2023, we have updated our Code of Conduct.

# Questions tagged [rigid-body-dynamics]

The study of the movements of a collection of connected bodies subject to external forces in the absence of deformation. This tag should be used for questions on the analysis of 2D/3D dynamics of rigid bodies, do NOT use this tag because your question contains a rigid structure.

167 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
1 vote
46 views

### Lagrangian preserve it's form for rigid bodies

Lagrangian for a particle moving under influence of conservative force given by $$\mathcal{L}=T-V$$ that is Kinetic energy minus Potential energy. Now for a system of particles I expect the same form ...
1 vote
38 views

### Tension on a massless string holding a semisphere in place

I am having trouble solving this. The problem is the following: Suppose a semisphere of radius $a$ (with its center of mass at $h = \frac{3}{8}a$) of mass $m$ located on a sliding surface. A massless,... 1 vote
160 views

### Pitch in Screw Motion of Rigid Body

Does anyone know how to prove these statements?
1 vote
346 views

### The torque in Euler's equations for rigid body rotations

In Taylor's Classical Mechanics, it is said that the equations are generally difficult to use because the components $M_1,M_2$ and $M_3$ of the applied torque as seen in the rotating body frame are ...
1 vote
164 views

### Are the ideas of angular velocity, angular acceleration, angular momentum, torque, etc only helpful for rigid bodies?

For rigid bodies, all the particles can have different linear velocities but the same angular velocity, so it makes it convenient to talk about the angular velocity instead. From there, we get to ...
1 vote
50 views

### Does gimbal for education exist?

I have been looking for a gimbal for a long time. Something similar to what you see in the book. However, I have had a lot of problem to find something similar. All my search results end to %95: ...
1 vote
458 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
134 views

### The Ehrenfest paradox and materials science

There are many questions on the Ehrenfest paradox but I couldn't find a duplicate (which may stil exist). The rim of a rotating disc would be Lorentz-contracted as seen from a non-rotated observer ...
1 vote
51 views

### Equivalent fictitious forces on rigid body

I know that when I study the motion of a rigid body from a non-inertial frame, I have to take into account the fictitious forces. However, it is not straightforward to find the resultant force (and ...
1 vote
81 views

### Is there a fixed orientation of center of mass axis about which all unconstrained rigid bodies rotate?

I just learned that an unconstrained rigid body always rotates about its center of mass. But there could be many axes that could pass through the center of mass. For example, let's consider a rod ...
1 vote
46 views

### How many illusionary axes of rotation can coexist?

Consider the answer to this question: How many different axes of rotation can coexist? Any rigid body, at any time, can only be rotating about one instantaneous axis of rotation. Now, that ...
1 vote
21 views

### Accion response calculation on tilt steering kick board scooter

Hi I am designing a home made kick board scooter, need to understant the behaviour between the board angle and the turn angle. In a classic sakateboard the foot action is transformed to turn angle, ...
1 vote
654 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
89 views

### Ideal geometry for a shaft terminating thrust bearing

Following this PyDy example, I'm trying to understand the problem set 3.10 of the book: Kane, Thomas R., and David A. Levinson. Dynamics, theory and applications. McGraw Hill, 1985. page 272 (292 ...
1 vote
71 views

### Insufficiency of Newton's third law to solve constrained motion problems

In The Variational Principles of Mechanics Lanczos describes what he calls 'vectorial mechanics': the process of solving mechanical problems by recourse to the immediate consequences of Newton's laws, ...
1 vote