This week Lena and Brian explore lenticular plastic — which contains many tiny cylindrical lenses — to play some cool tricks with light. This special plastic defocuses light along one axis, and is the basis of the LSOP experiment “Straw Crossed”.
Beau shares one last experiment with Heather before he heads off to medical school. “Muscle Memory” uses nitinol wire; sometimes called memory wire, nitinol is a nickel-titanium alloy that “remembers” its previous shape and reverts back to it when heated. The mechanism is an unusual phase change in the metal.
This week, we have a special video from our visiting science teacher Chris Chiaverina. Chris shows us how a microphone works and how to build “Slinky Sounds”, an awesome little experiment that makes some sci-fi sound effects!
This week, Rachel shows us how to make a vortex canon. This simple device shoots rings of air, and it can be made any size from tiny to gigantic!
The week Rachel shows us this awesome experiment using a wireless baby monitor and a microwave oven along with some bottles of water.
Eva has an egg and a bottle. The egg will not fit in the mouth of the bottle. She uses two different methods to get atmospheric pressure to push the egg into the bottle. The first method uses hot water, some of which evaporates. The water vapor displaces the air inside of the bottle. When the bottle is cooled, the vapor condenses into a liquid, which decreases the pressure inside of the bottle. The second method is similar, but uses a small fire to heat the air inside of the bottle, causing the air to expand. When the flame goes out, the air cools, lowering the pressure on the inside of the bottle.
Continuing on our theme of atmospheric pressure, this week we experiment on increasing and decreasing pressure, and how it affects the air trapped inside of marshmallows.
Last week, we showed you how atmospheric pressure can be used to give a giant “bear hug”. This week, we use atmospheric pressure to crush a metal can.
A plastic bag is connected to a vacuum pump. Initially the air inside the bag pushes out with the same force as the air outside of the bag pushing in. However, when the air is pumped out of the bag there is nothing to counteract the atmosphere squeezing the bag against the bear.
Last time we saw that we can separate mixtures by using size and magnetism. This time we use density to separate a mixture. This process is used to separate different types of plastics so that they can be recycled.