Wednesday, September 17, 2014

SCAPTI Photos and Highlights

I am posting photos from a successful Southern California Advanced Physics Teaching Institute (SCAPTI) workshop. We had two week-long sessions this summer with around 40 teachers in attendance, about 20 at each session. Each teacher received an excellent goodie bag full of lab supplies and a thick binder filled with useful curriculum. 

Already looking forward to next summer!

A spinning aquarium demonstrates 
centripetal force

Hands-on Laboratory Instruction: 
in this case, momentum collision with photogates

Participants work in small groups 
and actually get to do the labs. 

Several demonstrations explained, 
as well as the physics behind them.

Two photogates can report to a single terminal

There is often time for one-on-one instruction on 

confusing ideas and finer details.

James Lincoln, MS, MEd, explains how

 torque is proportionate to radius.

Participants immediately apply the idea of torque to an introductory experiment.

The units of torque are worked out, answering a specific question.  It turns out they are not Joules, but Joules per radian.

Information on the next upcoming workshop will be found at

Monday, September 1, 2014

UV Light: Demos and Experiments

Ultraviolet Light: Demos & Experiments Video is organized into several sections, including Absorbing UV Light, Fluorescence and Ultraviolet Light, Three Colors of Ultraviolet Light (UV-A, UV-B, and UV-C), The Discovery of UV Light, the Mercury Spectrum, and Phosphorescence. 

Through this video, you will learn about UV (ultraviolet) light, and it might save your life. Why? Ultraviolet light is more energetic than regular light—we sometimes call it “ionizing radiation” because it has the power to ionize the electrons in molecules, like DNA, and cause damage. In the video, surely you will be interested to see an original sunblock demo!

Absorbing UV Light

UV light is invisible to us, but its energy can make other objects glow. You will see white socks glowing under UV light, but it is actually the detergent residue that glows, not the socks themselves.

It doesn’t always take UV light to make things glow. These liquids [below] will glow under a blue light, but not all will glow under a red light.

Blue and violet lights are different from other colors, because they are more energetic, higher in frequency. Their higher frequency light is absorbed and re-emited as lower energy light.

These plastic beads are sensitive to ultraviolet light, and below you will see them glowing and colorful and UV light and in sunlight.

However, you will see that under a pane of window glass [below], the beads no longer change color.

Flowers Transformed--Through an Insect's Eyes

The video is almost ten minutes long which makes it a double video, power-packed with information. You will want to pause and re-watch segments and demos.