Jul
28

Author:

Comment

electron potential lines

Mass, charge, and spin

From a relativistic point of view, mass-energy is the total amount of energy of a body as expressed in Einstein’s E = mc2. Individual particles may have mass….

Read More
Jul
28

Author:

Comment

big bang

Inflate, deflate — Will the universe end
in a bang or a whimper?

Most scientists currently think the cosmological Big Bang Theory is valid. In this view, the universe, including time and space, began with a massive explosion at an infinitesimal…

Read More
Jul
24

Author:

Comment

string theory

String theory made simpler

The Standard Model of particle physics has been widely accepted among theoreticians but the problem is that it doesn’t integrate all that well with Einstein’s Theory of Relativity….

Read More
Jul
23

Author:

Comment

sparkfun logic gate blocks

A hands-on way to learn
digital logic functions

Spark Fun offers a battery-powered experimenter’s logic block kit that provides a visual representation of digital logic gates. It includes the battery and logic blocks with LEDs showing…

Read More
Jul
21

Author:

Comment

free space impedance

The characteristic impedance of the universe

Does the universe have characteristic impedance? If so, what is its value? Answers begin to emerge as we consider these facts: 1. Characteristic impedance is an attribute of…

Read More

Featured

waveguide featured

Basics of waveguides

Monday, March 23, 2015

There is something almost comical about a waveguide – the notion that electromagnetic signals or usable power could pass through a hollow pipe and that techniques appropriate to…

oliver heaviside

Oliver Heaviside and Maxwell’s equations

Friday, March 6, 2015

Oliver Heaviside’s life, spanning the years 1850 to 1925, began and ended in squalid surroundings. He was never entirely free of the dark melancholy that characterized his private…

keithley handbook

Answer this 5-question quiz, win a measurement handbook

Thursday, March 5, 2015

What’s your test IQ? Answer this five-question quiz and be entered to win one of 20 Low Level Measurement Handbooks graciously donated to us by Keithley Instruments, a…

VFD simple schematic

Variable Frequency Drives: Viewing the DC Bus

Thursday, September 25, 2014

By David Herres In the field of motion control it’s often necessary to vary the speed of an electric motor and even reverse its direction of rotation. When…