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What do people actually mean by "rolling without slipping"?

newtonian-mechanics rotational-dynamics definition rigid-body-dynamics asked May 14, 2013 at 13:15

physics.stackexchange.com

20 votes

Do the BAC-CAB identity for triple vector product have some intepretation?

vector-analysis cross-product geometric-interpretation asked May 23, 2013 at 21:11

math.stackexchange.com

14 votes

Mechanical similarity in Landau

classical-mechanics lagrangian-formalism resource-recommendations asked Jun 29, 2013 at 17:49

physics.stackexchange.com

11 votes

Calculating Green's function from Dyson's series without normal ordering

quantum-field-theory perturbation-theory greens-functions asked Jan 14, 2017 at 12:30

physics.stackexchange.com

8 votes

What are the differences (if any) between the Dyson's series definition and the "in/out" definition of the $S$-matrix

quantum-mechanics quantum-field-theory scattering s-matrix-theory asked Jul 8, 2016 at 14:06

physics.stackexchange.com

7 votes

Example of an increasing, integrable function $f:[0,1]\to\mathbb{R}$ which is discontinuous at all rationals?

real-analysis integration examples-counterexamples asked Feb 6, 2013 at 10:42

math.stackexchange.com

7 votes

Definition of the Hamiltonian via Legendre transform.

functional-analysis transformation classical-mechanics asked Dec 4, 2013 at 7:10

math.stackexchange.com

6 votes

Effective mass in Spring-with-mass/mass system

homework newtonian-mechanics harmonic-oscillator spring asked May 17, 2013 at 14:13

physics.stackexchange.com

6 votes

Landau&Lifshitz's derivation of the law of entropy increase - clarification

thermodynamics statistical-mechanics entropy asked Mar 12, 2015 at 21:46

physics.stackexchange.com

6 votes

When (or what is the meaning of) $I \propto E^2$?

electromagnetism optics energy poynting-vector asked Mar 27, 2015 at 23:11

physics.stackexchange.com

Top Answers

If $f,g$ are continuous at $a$, show that $h(x)=\max\{f(x),g(x)\}$ and $k(x)=\min\{f(x),g(x)\}$ are also continuous at $a$

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Isn't D'Alembert's wave equation enough to see that Galilean transformations are wrong?

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What's the point of Hamiltonian mechanics?

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If $a>1$, prove that $\lim_{n \rightarrow \infty } a^n = \infty$

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Increasing a potential causes increase in energy levels

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Interpretation of "transition rate" in Fermi's golden rule

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Dispensing with the "a priori equal probability" postulate

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What is $\Delta t$ in the time-energy uncertainty principle?

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Why don't photons split up into multiple lower energy versions of themselves?

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What is the decay width and why is it given in the energy units?

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Why does the expectation value of an operator $A$ take the form $\langle A\,\rangle=\int{\psi^* (x) A(x) \psi (x) dx}$ in QM?

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Why can the pion decay into two photons?

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$\theta$ angle QCD technically natural

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Expression of kinetic energy in polar coordinates

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Proof of Liouville's theorem: Relation between phase space volume and probability distribution function

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How to derive $E=mc^{2}$?

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Understanding notation: Derivative with respect to operator

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How do I calculate the experimental uncertainty in a function of two measured quantities

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$\phi^{4}$ Propagator - Feynman Diagram: internal vertex that loops back to itself

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Does every regularization/renormalization approach gives running coupling constants?

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