The fact that light carries both linear and angular momentum is well-known to physicists. One application of the linear momentum of light is for optical tweezers, in which the refraction of a laser ...

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 ...

An international team of physicists has simultaneously measured the angular momentum and torque exerted by acoustic waves for the first time. It found that this ratio agrees exactly with the predicted ...

In the ideal scenario of a bicycle wheel on a frictionless axle, there is no external torque acting on the wheel once it is set in motion. This is why it continues to spin at a constant angular ...

Surprising as it may sound, 107 years after the introduction of general relativity, the meanings of basic concepts are still being worked out. More than a century after Albert Einstein unveiled ...

Researchers have created a nano-sized light mill motor powerful enough to drive micro-sized disks. With rotational speed and direction controlled by the frequency of incident light waves, this new ...