wednesday, december 9, 2015

On this day we did a second experiment on light and heat and it again involved the use of a flashlight.  What it did not use was a thermometer but instead we used something called a radiometer.  We also used the Chrome Books for the brochure project in social studies.  But first, we did the warm-up.  There is a typo that I did not catch until after it was printed (there are two number eights).

A radiometer looks like a weather-vane with four panels inside a near-vacuum.  Each panel has a white side and a black side.  When a light shines on the white side of the panel, the panel either doesn't move or it will move slightly towards the light source.  

When light energy is focused on the black side, they spin.  If the light source is consistent the panels will start slowly and pick up momentum until they are spinning rapidly.  I will bring this back up in January since it involves light absorption.  

As a finale, I shined a powerful halogen spotlight on mine and it immediately spun fast. More on this next month.

We also used the Chrome Books to work on the brochure, which is due next Thursday.  I am going to allow plenty of time in class.  While we will have a science quiz on Friday, it only consists of 12 questions and I am very confident that the students will do quite well.

​Below is a slideshow of the students in action.