November 19, 2008
Yes, a needle can float but it is not easy.
We needed a magnetized needle to be able to use it as a compass.
One of the projects today was to find out where North is to set up the wind vane.
Another project was to find out how barometer work
and how to make one.
We checked that the indicator does move up if the air pressure is increased
by placing it in a container and pressing down on the lid.
Another project was to make a rain gage.
First we checked out which LEGO pieces would float. All did somewhat.
We made a rain gage that worked using a cork and a paper for marking the scale.
As the rain depth increases the indicator end goes down.
We made the scale out of LEGO pieces.
When the air pressure goes higher the indicator goes up.
Since we could not make a LEGO box for real today we used LEGO CAD.
That box would fill in the cup position in the weather tools model.
