Questions tagged [classical-mechanics]

Classical mechanics discusses the behaviour of macroscopic bodies under the influence of forces (without necessarily specifying the origin of these forces). If it's possible, USE MORE SPECIFIC TAGS like [newtonian-mechanics], [lagrangian-formalism], and [hamiltonian-formalism].

Classical mechanics refers to the classical (i.e., non-relativistic, non-quantum) study of physics. Three major formulations of classical mechanics are Newtonian mechanics, Lagrangian mechanics, and Hamiltonian mechanics. The latter two are rather useful in extensions to Classical Mechanics; Special and General Relativity, Quantum Mechanics, and beyond. Rotational dynamics, Statistical Mechanics, and Fluid Mechanics are subsets of Classical Mechanics.

However, the broader term, is often also used for and , as the also use the .

When to Use this Tag

Use when discussing general concepts of classical mechanics, i.e. the behaviour of macroscopic bodies under the influence of forces (without necessarily specifying the origin of these forces).

Use this tag only if , , , , , and the like are too specific. In general, you should not use together with or .

Overview

Classical mechanics is the study of the movement of bodies under the influence of forces. In absence of either movement or forces, the subtopics and arise, whereas the ‘complete’ subject is often dubbed dynamics.

For point particles/bodies, there are three equivalent approaches to deriving the trajectories of said bodies: based on Newton’s Laws, based on the variational principle and following from Legendre transformations of Lagrangian mechanics.

More advanced subtopics are for the study of moving many-body fluids (liquids, gases), for the derivation of macroscopic laws from microscopic principles (often making use of the Hamiltonian formalism) and for the study of rotating solid bodies.

Textbooks

  • Structure and Interpretation of Classical Mechanics, by Sussman, Wisdom, Mayer.

  • Physics for Scientists and Engineers with Modern Physics, by Jewett, and Serway.

  • Classical Mechanics, by Goldstein, Poole and Safko.

  • Mechanics, by Landau and Lifshitz.

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Equations for bent paper

I have a paper which lies on a flat surface. The paper is fixed on one side and the opposite side can slide in the direction of the opposing side. As side end slides toward the other, a "bump" forms. I want to know what the solution is to the shape…
Krumelur
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Will a ball slide down a lumpy hill over the same path it rolls down the hill?

Suppose I have a lumpy hill. In a first experiment, the hill is frictionless and I let a ball slide down, starting from rest. I watch the path it takes (the time-independent trail it follows). In the next experiment, the hill stays the same…
Mark Eichenlaub
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Does screwdriver length matter?

Everyone who deals with screws and screwdrivers knows that long screwdrivers are stronger than short ones. However, I can't find any relationship between length of a screwdriver and mechanical advantage. For a wrench, it's obvious: Long arms produce…
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Why is it possible to drive a nail into a piece of wood with a hammer, but it is not possible to push a nail in by hand?

It is possible to drive a nail into a piece of wood with a hammer, but it is not possible to push a nail in by hand. Why is this so?
asaa
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Meaning of the Poisson bracket as a coordinate transformation

Well, the Possion bracket: $ \{ A(q,p),B(q,p) \} \equiv \sum_{s} \left( \dfrac{\partial A}{\partial q_{s}} \dfrac{\partial B}{\partial p_{s}} - \dfrac{\partial A}{\partial p_{s}} \dfrac{\partial B}{\partial q_{s}} \right) $ is a coordinate…
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Is my boss wrong about our mechanical advantage from our pulley system?

I work on a drilling rig as a roughneck and we had a lecture today (at the office) about mechanical advantage in pulley systems. Now, I know that my boss is well educated in oil drilling, but my instincts tell me that he may have this one wrong. A…
Klik
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Why do we travel in a circle along the Earth?

I know that in order to travel in a circle I have to have a net centripetal force $F=mv^2/r$. I also know that my normal force and gravitational force cancel. How, then, am I traveling in a circle around the Earth as it spins?
Dargscisyhp
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What happens when a ball stops bouncing?

If I were to drop a bouncy ball onto a surface, each successive bounce will be lower in height as energy is dissipated. Eventually, however, the ball will cease to bounce and will remain in contact with the ground. What happens during that small…
PhiNotPi
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Car accident, put in park or neutral?

I was waiting on a red light the other day and was wondering. If I'm in my car, not moving and I see a car that's going to hit me from behind. Would I (my body) be safer if I put on the break or if I put the car in neutral? I assume there's no car…
the_lotus
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How did Feynman derive the physics of medallion vs. plate wobble rate?

I am referring to this: Within a week I was in the cafeteria and some guy, fooling around, throws a plate in the air. As the plate went up in the air I saw it wobble, and I noticed the red medallion of Cornell on the plate going around. It…
Graviton
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Which is more efficient: a larger wheel or a smaller wheel?

I'm designing a 2-wheeled cart that I plan to rig to a donkey for hauling work around a farm. I'm wondering if there are mechanical advantages to using smaller wheels (like 40 cm diameter) vs. using larger wheels (like 50 cm diameter).
wbevis
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A problem inspired by the ice hockey game

Question shortly: How far would a hockey puck slide in two different cases: The puck is sliding (translation) on ice and spinning on its flat surface. The puck is sliding on ice without spinning. Other conditions are the same in both cases.…
Martin Gales
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Driving on snowy roads

'tis the season as they say! It seems to me obvious that it's better to drive in high gear on snowy roads to reduce the torque. However, there are completely opposite advices being given on different sites: weather.com says "Use low gears to keep…
Sklivvz
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Three Pendulum Rotary Harmonograph

I'm trying to create a simulation of a three pendulum rotary harmonograph, the one you can see in action in this video or in these instructions. As you can see in the video, there are 2 pendulum with 1 degree of freedom each (one axis of movement)…
Saturnix
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Why can we inflate the balloon?

I have an elementary question: I know from experiences that human can inflate (or fill with water) the standard ballon or latex medical glove. But I know also that in rubber/latex there are a pores. Why can we do it? Which physical effect is…
Filip Parker
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