A straightforward demonstration of Newton's 3rd law, that forces are interactions and thus come in pairs.
How it works:
Two people, each sitting (cross-legged) on their own board, position themselves in the center of the track facing each other. Upon pushing against each other with their hands, they glide apart down the length of the track. Repeat this with one person turned around — the other person pushes on his/her back instead of pushing against each other with their hands. The ensuing motion down the track is exactly the same as before.
This is a concept question relating to Pascal's cask-bursting experiment. Imagine the experiment inverted—literally! Attach a 20-ft length of tubing to the opening of a can full of water. Turn the can upside down and raise it high. Will the water stay in the can, or will it run out? Will atmospheric pressure hold up the column of water in the tubing? What will happen? Have the class vote.
The interactions of the various radiations with matter are unique and determine their penetrability through matter and, consequently, the type and amount of shielding needed for radiation protection. Being electrically neutral, the interaction of gamma rays with matter is a statistical process and depends on the nature of the absorber as well as the energy of the gamma. There is always a finite probability for a gamma to penetrate a given thickness of absorbing material and so, unlike the charged particulate radiations which have a maximum range in the absorber...
Mechanical properties of some materials change dramatically with temperature. These changes have entertaining effects on everyday objects by taking them from room temperature 300K to the temperature of liquid nitrogen 77K.
How it works:
Place your everyday objects in a dewar of liquid nitrogen for several minutes (at least until the LN2 stops boiling). Some examples to use:
1. Rubber gloves freeze solid and shatter on impact with floor. 2. Use a banana to hammer a nail into wood 3. Frozen...
A light bulb is lit when the conductivity probe is immersed in an ionic solution.
The solutions are all in labeled 250ml beakers. All are about 150 ml of 0.1M sol'n. In order, the solutions are: tap water, distilled water, sodium chloride, sucrose, acetic acid, hydrochloric acid, sodium hydroxide, ethanol, and barium sulfate. (See video: http://youtu.be/4WillWjxRWw?hd=1)
The simple conductivity tester is on the bench, for the instructor to plug in. An 800ml beaker with 400 ml of distilled water is provided as...