Classical physics Definition and 221 Threads

In Rigid body rotation, we need only 3 parameters to make a body rotate in any orientation. So to define a rotation matrix in 3d space we only need 3 parameters and we must have 6 constraint equation (6+3=9 no of elements in rotation matrix) My doubt is if orthogonality conditions...

Thanks in advance!

I try to justify time-reversal symmetry in a very simple classical problem; Free Fall. The position, ##x##, and the velocity, ##v## are obtained versus time from the equation ##-g=\ddot x##. So, if we consider the primary conditions as ##t_0,x_0,v_0## it is clear that...

Shouldn't the equation be x' = x + (v')(t) instead of x' = x + (v)(t)?

I'm looking for full solutions to the Weidner/Sells series, published in the 1960's. I am not a student (in the usual sense) now, but had the W/S series as the text when I took freshman physics in 1965-66. I doubt that any school is using W/S now (so there's no trying to cheat on problem...

Hi, Can we derive an equivalent concept of quantum fluctuation in classical physics using correspondence principle? Also, how can we account for transfer of energy back and forth at the quantum and classical border? Thanks

I've managed to thoroughly confuse myself. Before Minkowski came along and combined 3-dimensional Euclidian space and time into Minkowski spacetime, I was under the impression that we only dealt with three dimensions and that time was just a universal parameter. Thorne and Blandford write...

I am a physics graduate student, also a physics enthusiast.I prefer Mathematical Physics, and often do some related research.Like everyone of you, I also have a strong interest in physics, and I hope to generate more new ideas and broaden my knowledge through exchanges with you.

As the tittle say. I've been out of touch with many branch of non-quantum non-relativistic physics and I would like to know what people that work in these areas would say are the most important or interesting current trents of research in classical physics.

Hello! I'll be entering my second semester of my junior year of my Physics Degree. My uni doesn't have a bad physics program, but it's really small so I have to take my upper level classes as soon as they're offered or I won't take them for another 2 years or so. They are on a cycle so I will be...

I tried to solve this problem and this is what I could come through: When the object is moving, the force acting on object is the frictional force, so, it got to be μmg. So, F = ma and as F is μmg μmg = ma μg = a So, to find out the magnitude of the initial velocity v given to the smaller...

Morning all I've recently come across a problem where I get conceptually but cannot apply mathematically if that makes sense. I understand the position of the third mass must be at the equilibrium point of ##m_1## (##9.0×10^{24}kg##), so ##\Sigma F = 0## right? And not even necessarily zero...

As a Computer Programmer, it's hard to wrap my head around Quantum Entanglement and non locality being explained in the context of Classical Physics. In other words, if the universe at it's core is physical where does Quantum Entanglement fit within a physical picture of reality? There's been...

Question.

Is classical physics independent from quantum physics? Or is classical physics an approximation derived from quantum physics? Is it dependent on interpretations? What quantum interpretations support the latter above?

The particle is moving under a force field with the potential energy equation described above. I find it logical that Newton's Laws can be used as in the question itself it is stated that the velocity is quite small and we could approximate its subsequent motion via the notions of Classical...

I'm reading Mechanics by Landau and Lifshitz, chapter IV, and trying to understand how in a (closed) center of mass system, with randomly distributed and oriented particles that disintegrate, "the fraction of particles entering a solid angle element ##do_{0}## is proportional to ##do_{0}##, i.e...

Reading the interesting book "Groups_and_Manifolds__Lectures_for_Physicists_with_Examples_in_Mathematica", in the introduction it is stated: (...) we have, within our contemporary physical paradigm, a rather simple and universal scheme of interpretation of the Fundamental Interactions and of...

I am starting to learn classical physics for my own. One exercise was, to calculate the vector r (see picture: 1.47 b). The vector r is r=z*z+p*p. I don’t understand this solution. My problem is: in a vector space with n dimensions there are n basis vectors. In the case of cylindrical...

I don't know where to put this but it is a question which is bothering me. From the perspective of a physicist who wants to generate new theories, what's the value in spending significant time learning classical theories? People slave always at books like Jacksons Electrodynamics but it's not...

Are there any? This Wikipedia article https://en.m.wikipedia.org/wiki/List_of_unsolved_problems_in_physics Only lists one under classical mechanics: Singular trajectories in the Newtonian N-body problem: Does the set of initial conditions for which particles that undergo near-collisions gain...

Homework Statement Homework Equations F= ma or F= md^2x/dt^2 The Attempt at a Solution I know that this second order differential is non linear. I attempted to solve the problem as -k/x^2 = md^2x/dt^2 but I'm getting trouble since it is a second order ODE and I haven't learned how to solve...

I would really appreciate if someone could advise me whether the system below is a scleronomic or a rheonomic mechanical system, or a mix of both. If we consider the first pendulum, the constraint is fixed which leads to a scleronomous case while the constraint of the second pendulum is not...

Hi! As the title suggests, I am searching for some good problem books with really challenging problems for classical physics, more precisely on the topics of electricity and elecromagnetism, geometrical optics and wave optics, thermodynamics and analytical mechanics. When I say challenging I...

How can I find the relation between the radiance and the energy density of a black body? According to Planck's law, the energy density inside a blackbody cavity for modes with frequency ##\nu \in [\nu, \nu + \mathrm{d}\nu]## is given by $$ \rho(\nu, T)\mathrm{d}\nu =...

Where in this though-experiment do I get it wrong? Even though no mass can travel faster then c, maybe information can? And I'm not talking about quantum entanglement etc. Consider a pipe, filled with balls that are very tightly arranged. If I push the outermost ball on one side of the pipe...

Homework Statement Refer the given image. [Prob 2.9] Homework Equations F=ma The Attempt at a Solution I drew the normal vector perpendicular to the surface of the cone and resolved it as ##Nsin\theta=mg## ##Ncos\theta=\frac {mv_{0}^2} {r}## where ##v_{0}## and ##r## are the speed and radius...

For example F=ma means that the definition of force is m*a or the quantity of left side equals to the quantity of right side or both ? or kinetic energy..we know K=1/2mu^2 but is this the definition of kinetic energy or just the formula to calculate it ?

A particle of mass m in xy plane is attracted toward the origin with the force $$\begin{align}\vec{f} = - \frac{k^{2} m}{r^{6}}\vec{r}\end{align}$$ where ##\vec r## is position vector of particle measured from origin. If it starts at position ##(a,0)## with speed $$v=\frac{k}{\sqrt{2} a^{2}}$$...

Ive always been fascinated by the subject, and i absolutely love learning new concepts, especially when theyre intriguing and brain-twisting, but i can never seem to grasp onto the depths of concepts for a long time. Suppose, if i stop working out problems for a week or so on a particular...

Hi, I know that in an elecric field the potential energy ##E_{pot}## is equal to the potential ##V## times the charge ##E_{pot}=q V##. Here my problem: I know that the potential energy of a spring is ##E_{pot}= \frac{1}{2}kx^2##. In my theoretical physics book i read also that the potential is...

All copyright strictly reserved to Prof. Balakrishnan and NPTEL, Govt. of India.

All copyright strictly reserved to Prof. Balakrishnan and NPTEL, Govt. of India.

All copyright strictly reserved to Prof. Balakrishnan and NPTEL, Govt. of India.

All copyright strictly reserved to Prof. Balakrishnan and NPTEL, Govt. of India.

All copyright strictly reserved to Prof. Balakrishnan and NPTEL, Govt. of India.

All copyright strictly reserved to Prof. Balakrishnan and NPTEL, Govt. of India.

All copyright strictly reserved to Prof. Balakrishnan and NPTEL, Govt. of India.

All copyright strictly reserved to Prof. Balakrishnan and NPTEL, Govt. of India.

A question I've had about the black body problem and classical physics in general has to do with the conservation of energy. One of the first things you can derive in classical mechanics is that for a conservative force the total energy of the system doesn't change. However, one of the typical...

If you have a rectangular box connected on 3 sides with strings, and you hold all the strings together at a point, with your hand; then you put a weight in the center of the box, which is open, would the tension on the strings differ than if you put the weight at a corner. Please describe it to...

Hello, It is considered that the time is continuous in classical physics, but it sounds paradoxal to me, let me explain. Let a particle inside a galilean frame of reference. This particle can only be measured either at rest, either in motion, but never simultaneously at rest and in motion...

Homework Statement Dimensional formula for 'the square of the distance between two bodies' in universal gravitation and 'distance from the axis squared' in moment of inertia. Is L^2 is the dimensional formula for both the distances in the above two cases? Homework Equations F=Gm1m2/d^2; moment...

I plan on building a swing set for my daughter, and I always loved the feel of a good tall swing. I like the long range of motion, the nice glide ... but is there such thing as too tall? I was planning on going about 14' off the ground with the cross beam .. then I figured, well, let's go with...

Hello guys, I programmed a physics simulation where a particle with some initial conditions bounces off the walls of a 2d container. The simulation also includes gravity in the y-coordinates. The aim of the project is to produce a visual animation and further on include more particles and...

Is classical physics more than just the quantum physics of a large number of particles and quanta? Thanks for your thoughts.

Hi, I was wondering, as in the Bachelor's degree curriculum there is no SR course, for one who is interested in theoretical physics (as me), would do it alone, perhaps with texts such as Rindler or Synge ...? Thank you in advance !

Hey guy, I'm a just new in physics and i want to self-teaching it. But i don't know what calculus i need for classical mechanic. Pleas help! And if you suggest me a book can you pleas help to send me a link (and the book must be in pdf pleas) Thank

Hi there, I've been trying to solve the following problem, which I found looks pretty basic, but actually got me really confused about the definition of angular momentum. Problem The trajectory of a point mass m is described by the following equations, in spherical coordinates: r(t) = r_0 +...

Hi I've been wondering about Boltzmann's equation S = k ln W Where W is the number of different distinguishable microscopic states of a system. What I don't get is that if it's the position and velocity of a particle that describes a microstate doesn't it mean that W would be infinite...