# Blog Profile / Dot Physics

URL : http://www.wired.com/wiredscience/dotphysics Academics / Physics 423 1.6 July 11, 2011

## Blog Post Archive

### The Bullet-Block Problem With a Twist

Check out this entirely awesome video experiment from Derek Muller (Vertasium youtube channel). The video shows the classic problem of a bullet fired into a block of wood. If the bullet is fired below the block and is embedded in...

### Welcome to the Fall Semester: Student Edition

I am going to set up a situation and then ask a question. Ready? Ok, suppose you just joined a local gym – you know, a place where you go to work out. Now for the question. Why did you...

### Why Do Solids Expand When Heated?

Just about every (but not all) solids expand with an increase in temperature. Why? Before going to the answer, let’s look at a common model of a solid – the ball and spring model. In this model, solid matter is...

### Welcome to the Fall Semester: Faculty Edition

It’s time for the beginning of Fall classes. Here are some random thoughts for faculty to consider during this time. Just a quick note: nothing here is new. I have probably gone over all of these things before. I will...

### How Sensitive Are Sharks to Electric Fields?

It turns out that sharks (and some other fish) can detect electric fields. This 6th sense is called electroreception. I don’t know much about sharks (well, I think they’re cool), but I do know something about electric fields. According to...

### Hyperloop Physics Questions and Answers

The best part of the Hyperloop is that it’s the coolest real world physics problem. What’s the Hyperloop? Who knows for sure, it is some type of transport that could get from LA to NY in just 45 minutes. Here...

### How High Can You Toss Your Phone?

This seems to be the popular thing right now. Basically, there is a an app that records the time your phone is in free fall. From this, it gives you the height that you tossed it. Yup, apparently the new...

### Modeling Angry Birds Star Wars Blasters

I told you I would do this – make a model of a blaster bolt from Angry Birds Star Wars. Really, this is the only way to make sure you know what’s going on with the blaster bolts. If I...

### Here Are Some of My Favorite Mistakes

I like the old saying about computational models: You can pick two of the following three things: Fast, Accurate, Cheap. So, you could calculate the interaction between two hydrogen atoms, but if you want it super accurate it will either...

### How Short Should You Cut Your Grass?

I don’t know about you, but I mow the lawn quite often. In the summer months, it is a bit more often than I care for it to be. “Maybe you should just cut it shorter. That way you will...

### Why Does This Man’s Head Appear Off His Body?

This is not the cool picture. I made that with a LEGO minifig based on this awesome image of a guy in a pool – http://i.imgur.com/im37Rwn.jpg. Yes. You must click that link and see the awesome picture. What’s going on?...

### Video Analysis of an Underwater Bullet

I can just imagine what Destin would say. “Hey, how about I take an AK-47 and shoot it underwater? I can record the motion with a high speed camera. It will be fun.” Yes. That’s exactly what Destin from the...

### How Do You Find the Density of Saturn?

In my previous post about a floating Saturn, I hinted that I could write about the methods we can use to find the density of Saturn. Oh, and once again, the density of Saturn is lower than the density of...

### Blasters in Angry Birds Star Wars

It was just a matter of time, wasn’t it? You knew that at some point I had to look at Angry Birds Star Wars. Why now? Well, I didn’t want to look at any Angry Birds physics until I finished...

### No. Saturn Wouldn’t Float in Water

Is there a cooler object in the sky than Saturn? Maybe Jupiter, but I like Saturn a little better. If you know what you are looking for, you can see the rings of Saturn even with a pair of binoculars....

### Browser Tabs and Battery Life

I’m sure I heard something about battery life and browser tabs on the Tech News Today podcast. I just can’t find the exact episode (or maybe I saw it somewhere else). Anyway, in my imagination there is a story about...

### Why Are Human Powered Helicopters So Big?

Recently, a Canadian team won the \$250,000 Sikorsky Human Powered Helicopter Prize – details here. The prize is for the first human powered helicopter that can hover for 1 minute and reach an altitude of 10 feet while staying in...

### What Is the Landing Speed of a Drone?

So a drone lands on an aircraft carrier. Pretty cool, right? Well, it’s cool until you realize that this is just the first steps toward robots taking over the world. But yes, it’s cool. The best part is that this...

### Is Light a Wave or a Particle?

It’s in your physics textbook, go look. It says that you can either model light as an electromagnetic wave OR you can model light a stream of photons. You can’t use both models at the same time. It’s one or...