Author Archives: Matthew

In part 1 and part 2, we introduced the reverse sprinkler problem and tried to gain some theoretical insight. In this final part, we will simulate five different sprinkler designs and interpret the torque results.

In part 1, we introduced the reverse sprinkler problem and attacked the most ideal case, ignoring factors such as pipe diameter. Now we will perform a more general analysis.

A short version of this post series is also available as a YouTube video here. The reverse sprinkler is a physics problem that has long been a source of confusion and debate. It is sometimes known as the Feynman sprinkler problem … Continue reading →

Is it possible to build a wind-powered vehicle that can continuously travel faster than the wind, in the same direction as the wind? Like the airplane-on-treadmill problem and the Feynman sprinkler problem, this question has spawned endless Internet arguments. Continue reading →

Electromagnetic radiation is something that has often eluded my intuition. Electrical engineering depends on numerous abstractions: current flowing in wires like a fluid, capacitance/inductance in lieu of near field interactions, antenna theory to model far field interactions, etc. These abstractions … Continue reading →

You may have heard of the incident where a helium leak suddenly disabled many iPhones at a medical facility. The root cause — tiny MEMS oscillators being susceptible to helium leaking into their hermetically-sealed casings — is interesting but not … Continue reading →

For a long time I thought of the H field as being generated by free currents only. The problem with this view is that it leads us to make erroneous assumptions. We know from the definition of H that:   … Continue reading →