# magnetic

### Could I build a lightning detector?

A while ago, we had a ton of lightning. As a bonus, it always happened in the middle of the night. I love sleeping where it sounds like I am on the front line in WWI - no, I don't. But, while lying awake waiting for the next BOOM I thought of something. Instead of just counting the time between flash and boom, maybe I could make a lightning detector. For mere mortals, the first step might be to google "lightning detector". I don't want to do that. What fun would that be? I did look up something. The current in a typical lightning strike is on the order of 30,000 amps. How could I…

### What is this #2: Answer

Reader Fruity was the first to correctly name this device - on just the 9th comment. Impressive. Honestly, when I found this thing I had no clue. I asked other physicists and none of us were sure. However, I did find the answer. Let me show you my secret. I don't know how old this thing is, but it is old. When I open it, my nose and eyes get all tingly - probably from the mold. Here is that apparatus in the book (tome): I can't show you the whole page because it has other stuff of awesomeness that I want to show you later. But, I can show you the description for that item. I am…

### Right Hand Rule: Don't hurt yourself

It is that part of the semester where the Right Hand Rule (RHR) comes out. Really, the best part is the students taking the tests. They make all these funny motions with their hands. That makes tests more entertaining (for me) than they usually are. What is the RHR? Suppose I have two numbers. Maybe these two numbers are the length and width of a piece of paper. Now suppose I need to multiply length times width to get the area (A = L x W). Simple - right? But that is multiplication for scalar variables. How do you multiply vectors? There are two common operations you can do with…

### Power lines disrupt the magnetic alignment of cows and deer

Farmers and herders have known for centuries that herds of cattle have an uncanny ability to all point in the same direction. Last year, a group of German and Czech scientists discovered the reason behind this alignment - unbeknownst to humans for thousands of years of domestication, these animals have a magnetic sense. The team used Google Earth satellite images to rule out alternative explanations like the wind and the sun, and show that cow and deer herds tend to point towards magnetic north like a living, hoofed compass needle. Now, the same team have found that high-voltage power lines…

### A Star with a Napoleon Complex?

No, really, I can hang with the big boys! Although this is usually something we hear from people who are seemingly out of their league, due to diminutive stature, here on Earth: (Muggsy Bogues is awesome.) Apparently, there are stars out there that have the same Napoleon Complex. According to this Press Release, a star only 1% as bright as the Sun just released a burst of energy as powerful as 1000 solar flares! Now, that link is only too happy to provide you with an artist's rendition of what happened: But let's compare this with real stuff, instead. Our Sun has a magnetic field that's…