Why does the action $S=\int L dt=\int (T-V) dt$ have to be minimised (or maximised) to produce Newton's Second Law?
63069
Why the Principle of Least Action?
39041
work done is zero if displacement of point of application of force is zero but why can't we assume forces on COM and its displacement
12818
In calculating work done by a constant force over a constant distance, why doesn't the subject's initial velocity matter?
40740
Why force $F$ is $ma$ but not $md$ or $mv$? How can I observe and understand "force" in real life?
70880
Invariance of canonical Hamiltonian equation when adding the total time derivative of a function of $q_i$ and $t$ to the Lagrangian
25779
Constants of motion vs. integrals of motion vs. first integrals
142353
Why in Newton's law of gravity, we do $M_1 \times M_2$ and not $M_1 + M_2$?
93588
Based on newtons third law
94173
Deriving the Lagrangian for a free particle
24150
Newton's third law does not apply to the kinetic energy formula?
125883
Moment of inertia: why $\mathrm{dI}=r^2\mathrm{dm}$ instead of $\mathrm{dI}=m\mathrm{dr^2}$?
98358
A variational problem with a lagrangian , what is the lagrangian?
155740
Newton's Law of Graviation: Why $G$ and not e.g. $\dfrac{1}{4\pi G_0}$?
62692
Retrieving Maxwell's equations from the minimum action principle
74367
Newtonian mechanics: massless particles
48930
Least-action classical electrodynamics without potentials
135471
In wave motion of a string both kinetic energy and potential energy are minimum at $y=y_\text{max}$ then why does the string come down again?