Swinging Bob
I was introducing general relativity to my class yesterday and wanted to show some examples of how different experiments would be in both g field and accelerated frames of reference, so I made this pendulum...
Cheap but not cheerful
I mentioned a few posts back that I was waiting for the arrival of 36 mini slinkies so I could hang them off the ceiling and make a wave by setting them in motion one after the other. Today they arrived...
International wave
Today I tied 12 balls to the ceiling on 1m long strings to see if I could make a pendulum wave for real. I got 6 student to hold two balls each and release them one after the other. Not anywhere near...
Correcting vision
When I was at school we studied a topic called "defects of the eye", I always thought that this title wasn't very politically correct so am glad to see that the new syllabus will include the topic "correcting...
Long wave goodbye
After making the pendulum wave a week or so ago I have been wondering about making a longitudinal version. The problem again was how to release the pendula at different times. I used a similar solution...
Malus through the looking glass
I'm still playing with the little bits of polarising plastic I bought from eBay. I was wondering if I could verify Malus' law by photographing my computer screen through a piece of polariser. My first...
Tsunami in a bathtub
Today my first years did the resonance in a bucket experiment. As usual they couldn't believe that the speed of the wave didn't depend on when they pushed the side of the container. One group wanted to...
Cross Poles
The other day I wanted my class to look at my computer screen through a polariser but I could only find one bit of Polaroid. With 18 in the class it takes a long time to pass around the precious bit of...
Sherlock Holmes in black and white
Today I had an idea for an extension to the diffraction in a CD practical. How about comparing diffraction in a CD with diffraction in a DVD? So I fetched a DVD from the other room. Sherlock Holmes. We...
The Car
You wouldn't believe how long it took to create this rather basic looking animation on the left. In fact unless you enter the blog you won't see anything at all. I was inspired by watching the hand drawn...