A Bed of Nails
Description: Special caution should be taken when sitting down or getting up from a bed of nails. In this video, Steve Spangler used a motor to lift the entire bed of nails up and down safely. Each of the nails is pushing on the participant but since there are so many nails the force is distributed safely between all of the nails. This demonstration could be used in any physics unit discussing forces and pressure.
Web Resource: Bed of Nails - Wikipedia
Amazing Rube Goldberg Machines
Description: Rube Goldberg machines are named after American cartoonist Rube Goldberg who drew complicated steps involved in doing a fairly simple task (like pouring milk in a glass). Students can study these machines, or build their own, to show how energy can be converted through a series of interactions. In lower elementary classes they might be shown or built to show how pushes or pulls can change the motion of objects. As they move through school they should start to identify specific collisions, interactions, and conversions of energy.
Web Resources: Rube Goldberg Machines - Wikipedia
Slow Motion Golf Ball Collision
Description: In this dramatic slow motion video a golf ball collides with a piece of steel showing a large amount of compression. Different golf balls are designed to have varying amounts of compression based on the desired behavior of the ball. In a kindergarten class golf balls or baseballs are great examples of pushes causing changes in the motion of an object. In the upper grades this could be a great example of a collision. Students could investigate the behavior of different golf balls (or clubs) and even do some designing themselves.
Web Resource: Golf Ball - Wikipedia
Magnetic Cannon
Description: The magnetic cannon contains four spaced neodymium magnets in a channel. Two balls bearings are placed between each ball bearing. When a new ball bearing is introduced a transfer of energy occurs and the final ball bearing leaves with a higher initial velocity than the first. This is a great phenomenon for studying transfer of momentum and the energy of an object based on its position within a magnetic field.
Web Resource: Magnetic Challenge with Bozeman Science
