classical-physics

How do you portray momentum in space accurately? Columnist Chanda Prescod-Weinstein takes a look at the origins of our understanding of motion, which runs from Isaac Newton back to the Zhou dynasty a millennia ago

The Inverse Cube Force Law Posted by John Baez Here’s a draft of my next column for the Notices of the American Mathematical Society. It’s about the inverse cube force law in classical mechanics. Newton’s Principia is famous for his investigations of the inverse square force law for gravity. But in this book Newton also did something that was rarely discussed until the 1990s. He figured out what …

Working in quantum many-body theory, I slowly learned that many key concepts and techniques have predecessors and analogues in classical systems and one-body quantum systems. Examples include Green's functions, path integrals, cumulants, the linked cluster theorem, Hubbard-Stratonavich transformation (completing the square), mean-field theory, localisation due to disorder, and BBGKY hierarchy . L…

Predicting Eclipses: The Three Body Problem Predicting Eclipses: The Three Body Problem Solar eclipse prediction has driven innovation across the history of science and mathematics, from the Saros cycle to Greek geometry to Newton’s calculus to the three-body problem. Explore All Videos Biggest Breakthroughs in Biology 2025 2025’s most surprising breakthroughs in biology included a finding that a…

Introduction The applicability of Newton’s second law in the oft-quoted “general form”  $$\begin{align}\frac{d\mathbf{P}}{dt}=\mathbf{F}_{\text{ext}}\end{align}$$ was an issue in a recent thread (see post #4) in cases of systems with variable mass.  The following example illustrates the kind of confusion that could arise from the (mis)application of Equation (1): A rocket is hov…

Are you a physics student in search of captivating and unique topics for your next paper? Look no further! In this blog post, we have created a comprehensive list of 203 original physics topics, covering Paper 1 and Paper 2, as well as many other areas of physics. Whether you’re exploring classical mechanics, astrophysics, electromagnetism, […]

(after Sonnet 130) The post Ode to Newtonian mechanics appeared first on Chalkdust .

In my previous post, I mentioned an exercise that I often give to my General Physics students that are learning about projectile motion. Using a PhET application, they found out that two different scenarios produced a projectile motion that has the same maximum height and same time of flight. I asked the students to figure out why. I decided to post the same question to ChatGPT. The result was a …

All moving objects have momentum. Another way to think about momentum is how hard it is to stop a moving object. It's harder to stop an object moving quickly than an object moving slowly. What is the momentum equation? All moving objects have momentum. Momentum is a vector quantity which means it has size AND […] The post What is Momentum? appeared first on Science Experiments for Kids .

Introduction In a previous Physics Forums article entitled “How to Master Projectile Motion Without Quadratics”, PF user @kuruman brought to our attention the vector equation  ##\frac{|V_0 \times V_f|}{g} = R## and lamented the fact that: “Equally unused, untaught and apparently not even assigned as a “show that” exercise is Equation (4) that identifies the range as the...

Isaac Newton is one of the few names that will forever be enshrined in physics history and that too with a lot of glamour associated. Contributions of none other physicist match his, well, probably Einstein's, or not even his!? The following are Newton's ten most well-known works that changed the world later on. Laws of motion 1. An object will remain at rest or move in a straight line unless act…

Faraday's Fields The word “field” appears for the first time in “On new magnetic actions” by Michael Faraday in 1846. Faraday was referring to a region in the vicinity of a magnet affected by some force. Forces, in mechanics, are actions that tend to maintain or alter the motion of a body or distort it. Faraday spent his life grappling with the mechanism by which the magnet supplied this apparent…

What Causes Inertia? Last time, we looked at the idea of a limit on the speed of light. We can only imagine two reasons that all physical motions are slowed (please let us know if you have other ideas): because other objects get in the way or because something clings to them. Today we’ll look into the cause of Newton’s observation that an object at rest or in motion remains so unless pressured ot…

Researchers from the Austrian Academy of Sciences, the University of Vienna and the University of Geneva, have proposed a new interpretation of classical physics without real numbers. This new study challenges the traditional view of classical physics as deterministic. In classical physics it is usually assumed that if we know where an object is and its velocity, we can exactly predict where it w…

These simple-looking equations went on to have great consequences and applications in science, society and technology. Let us take a look at the ten most influential formulae in physics (in no particular order) which have changed the course of history. Second law of motion The force, often intuitively described as push or pull, is actually the cause of acceleration in a moving particle. Without i…

Introduction Preface While browsing through unanswered posts in the Classical Physics Workshop, I came across a gem at the link shown below.  For the reader’s convenience, I have included (in italics) the OP’s statement of the question. Original problem https://www.physicsforums.com/threads/spacecraft-path-with-polar-coordinates.683210/ There is a circular gate rotating at a constant …

I just had to get this one. I found this last week during the members night at Chicago's Adler Planetarium. The people that I were with of course knew that this is referring to "force", but they didn't get the connection. So I had to explain to them that Newton's 2nd law, i.e. F=ma can be expressed in a more general form, i.e. F = dp/dt, where p is momentum mv. Thus F = d/dt (mv) Of course, I'm n…

This Insights article is about dissipative forces (friction, air resistance, viscosity…). Damping by friction forces is one of the concepts that is encountered earliest by physics students. The reason for its importance is that almost all moving objects in everyday life are affected by friction and air resistance, which is why Newton’s 1st law is...

My essay Explaining Rolling Motion raised some commentary about frames of reference and their equivalence when solving physics problems. I wish to pursue the idea of shifting one’s frame of reference because its use is relatively uncommon in introductory physics courses.   Students are asked to solve problems mostly in the (approximately) inertial frame of...

With the Sochi Olympics going on now, it is inevitable that articles on the physics of the various sports at the winter games will appear. This is one such article with an instructive video of Walter Levin explaining the physics of figure skating. Zz.