Introduction You might have seen figure skaters spinning around quickly and then tucking their arms to spin faster—or opening them to spin more slowly. This happens, thanks to a physics concept known ...

Step 1: Sit in the swivel chair and hold one hand weight in each hand. Step 2: Stick your arms straight out and have your friend or parent spin the swivel chair (Make sure the chair is not one that ...

When a magnetic material like nickel is zapped with an incredibly short laser pulse, it loses its magnetism almost instantly within femtoseconds, or a millionth of a billionth of a second. But physics ...

We’re all familiar with the magic of the Olympic games. Once every four years, the entire family sits down together to watch a selection of sports that many of us are not routinely exposed to. As a ...

When a magnetic material is bombarded with short pulses of laser light, it loses its magnetism within femtoseconds (10 –15 seconds). The spin, or angular momentum, of the electrons in the material ...

Schematic of a single photon with zero angular momentum (green) splitting into two photons (red) with either zero or opposite angular momenta (sketched through the spatially varying color), which adds ...

It's almost always the last topic in the first semester of introductory physics—angular momentum. Best for last, or something? I've used this concept to describe everything from fidget spinners to ...

In an introductory physics course, there are three big ideas. There is the work-energy principle, the momentum principle and then the angular momentum principle. I'll skip the work-energy principle ...

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