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 ...

Segment 4B: Conservation of Momentum We explain it qualitatively and mathematically. Segment 4B: Conservation of Momentum The law of conservation of momentum is explained qualitatively and ...

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 ...

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 ...

This course introduces the quantum mechanical concept of angular momentum operator and its relationship with rotation operator. It then presents the angular momentum operators, their eigenvalues and ...

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 ...

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 ...