# Simple Experiments with Friction

Now I get to do something with that force scale I built. I had a request some time ago to talk about friction. Friction is surprisingly complicated. When two surfaces rub against each other, why is there a friction force? The basic answer is that the stuff the two surfaces are made of (atoms) are…

# Lab: The Charge of an Electron

Not really. Here are the details (and some data) for the Millikan Oil Drop Experiment without the oil drop that I talked about previously (originally from The Physics Teacher – lucky you, it was a featured article so it should still be available (pdf)). The basic idea that Lowell McCann and Earl Blodgett from U…

# Circular Motion Lab

Sometimes it is difficult to come up with new labs. Ideally, a lab should show use some of the basic physics principles as well as have something the students can measure. What to do with circular motion? I don’t know how I forgot this, but here is a lab I used to do as an…

# Rutherford scattering toy, and more

My friend Konrad showed me this awesome toy he made. I know it doesn’t make sense yet, so let me explain. Basically, you take this marble and roll it down the tray through the pegs. The pegs sort of randomize where the marble rolls through the hidden section. Inside the hidden section, it looks like…

# More projectile motion than you can shake a stick at

I don’t really know what that title actually means. So, I have been having problems with my PASCO projectile launcher devices. I will just call them launchers (they are really cannons). In my previous post, I looked at the launch speed from a launcher shot horizontally and vertically. The problem was that I was getting…

# More Measurements of the Projectile Velocity

The last time I looked at this projectile motion lab, I was confused. My different methods for measuring the launch speed of the ball were not even close to being consistent. So, I am bringing out the big guns – video. I made a video of the ball shot both horizontally off the table and…

# Millikan Oil Drop without the Oil

I found this in the most recent issue of The Physics Teacher (September 2009). Surprisingly, there were several good articles in this issue. One article discusses a doable version of the Millikan Oil drop experiment. Maybe you are not a (or were not) a physics major, so you might not be familiar with how cool,…

# Labs to not do – mechanical equivalent of heat

Note to self: don’t do the mechanical equivalent of heat lab again. It doesn’t really work that well and there are better labs to do. So, what is the mechanical equivalent of heat lab? It is actually a pretty cool idea. Take and object and drop it. What happens to the kinetic energy the object…

# Measurement and Uncertainty – an example

I previously talked about measurements (some) when I looked at the uncertainty in the distance to the Sun. One of the simple ways of determining the uncertainty of a calculated quantity is to use the uncertainty of the measured variables and find the max and min that calculated quantity can be. The example I used…