Grim Reaper Does a Back-of-the-Envelope Calculation

I have a secondary super-villain identity. People on Google+ called me: Elke the Ripper or Master of the Scythe. [FAQ] No, I don’t lost a bet. We don’t have a lawn-mower by choice. Yes, we tried the alternatives including a reel lawn-mower. Yes, I really enjoy doing this. It is utterly exhausting – there is no…

How to Introduce Special Relativity (Historical Detour)

I am just reading the volume titled Waves in my favorite series of ancient textbooks on Theoretical Physics by German physics professor Wilhelm Macke. I tried to resist the urge to write about seemingly random fields of physics, and probably weird ways of presenting them – but I can’t resist any longer. There are different…

Non-Linear Art. (Should Actually Be: Random Thoughts on Fluid Dynamics)

In my favorite ancient classical mechanics textbook I found an unexpected statement. I think 1960s textbooks weren’t expected to be garnished with geek humor or philosophical references as much as seems to be the default today – therefore Feynman’s books were so refreshing. Natural phenomena featured by visual artists are typically those described by non-linear…

Space Balls, Baywatch and the Geekiness of Classical Mechanics

This is the first post in my series about Quantum Field Theory. What a let-down: I will just discuss classical mechanics. There is a quantum mechanics, and in contrast there is good old classical, Newtonian mechanics. The latter is a limiting case of the former. So there is some correspondence between the two, and there are rules…

The Falling Slinky and Einstein’s Elevator

I have not known that this toy has a name at all. The ‘spring’ that can walk down the stairs is called Slinky! We all know how the Slinky walks – but how does it fall? This video might come as a surprise! The authoritative article on The Falling Slinky is this one: Modelling a…

The Twisted Garden Hose and the Myth of the Toilet Flush

If you have wrapped your head around why and how the U-shaped tube in the flow meter (described in my previous post) is twisted by the Coriolis force – here is a video of a simple experiment brought to my attention by the author of the quoted article on gyroscope physics: You could also test it…

Intuition and the Magic of the Gyroscope – Reloaded

I am baffled by the fact that my article The Spinning Gyroscope and Intuition in Physics is the top article on this blog so far. So I believe I owe you, dear readers, an update. In the previous article I have summarized the textbook explanation, some more intuitive comments in Feynman’s Physics Lectures, and a new…

Physics / Math Puzzle: Where Is the Center of Mass?

On randomly searching for physics puzzles I have come across QuantumBoffin‘s site. The puzzle is about how to determine the center of mass of a body using the plumb line method, given there is some uncertainty due to experimental errors. You have found three plumb lines not intersecting in a single point; thus the three intersections of…

Random Thoughts on Temperature and Intuition in Thermodynamics

Recent we felt a disturbance of the force: It has been demonstrated that the absolute temperature of a real system can be pushed to negative values. The interesting underlying question is: What is temperature really? Temperature seems to be an intuitive everyday concept, yet the explanations of ‘negative temperatures’ prove that it is not. Actually, atoms have…

Why Fat Particles Radiate Less

I am just reading Knocking on Heaven’s Door by Lisa Randall which has a chapter on the impressive machinery of Large Hadron Collider. The LHC has been built to smash proton beams against each other: Protons, not electrons. Why protons? I stumbled upon the following statement: “But accelerated particles radiate, and the lighter they are, the more they do…

Is It Determinism if We Can Calculate Probabilities Exactly?

I set a stretch goal for myself: I want to force myself to keep some posts of mine short. As a fan of MinutePhysics I am launching a new category: Physics in a Nutshell. I am going to try to tackle a question that has bothered me for a while – hopefully briefly and concisely. ___________________________________ The question of…

Why Do Heat Pumps Pump Energy so Easily?

I know my posts are usually walls of text, but I am trying to improve! In his landmark physics course, the Feynman Lectures on Physics, Richard Feynman tries to explain what an explanation in physics actually is. You can always understand “the math” and follow a proof step-by-step. But deep, yet intuitive, understanding becomes harder and…