On an energized, intact circuit, you will read voltage across an OPEN switch when testing with a voltmeter. However, you probably won't read significant voltage across a CLOSED switch. Both sides of a closed switch are electrically identical (or at least very close). Therefore, there should be no movement of electrons between the leads of […]

I was listening to someone talk about air relative humidity the other day while looking at a psychrometric chart, and he commented that the chart ends down at freezing (32°F) because “all the water freezes out of the air at that point.” I think I made this Jed Clampett face: The psychrometric chart is designed […]

The year was 1774, and a man named Tom traveled the Atlantic from England to visit his friend Ben in Philly. Tom was 37 years old, and he had already been through a failed business and lost his wife and child during childbirth. He was a troublemaker by some accounts—a free spirit at the very […]