The strange world of electromagnetic waves! More videos at http://www.sixtysymbols.com/
========== Now Brady, here comes the bit that really gives you a headache...I'm going to show you how light can be polarized by sheets of Polaroid.This is a sheet of , it's polyvinyl-alcohol with iodine in it.In here are long molecules which are stretched outand conduct along this direction but they don't conduct that way.That's what your Polaroid sunglasses are made of.It reduces the glare of the road.I put this sheet on top of this overhead projectorand I put another sheet on top polarized the same wayand they absorb a bit of light.But if I turn this top one round, so that it is perpendicular,you can see you can kill off most of the light.So there is some turning backwards, all the way round,and now I'm going back again and you see it disappears.This is an off-cut, a bit chopped off from the bottom of this,and I can put it on top of these two...
