Sound- Rarefactions and Compressions

Principle: Sound travels in the form of successive compressions and rarefactions
Hold one of the ends stationary and pull or push the other end and observe what happens

Items Required to make:
Copper wire
PVC tube

Things To Know:
Equipment for generating or using sound includes musical instruments, hearing aids, sonar systems. A natural example of this is as a phase in a sound wave or phonon. Half of a sound wave is made up of the compression of the medium, and the other half is the decompression or rarefaction of the medium.

Trebuchet

Principle:In a second class lever the input is located to the far side of the bar, the output is located in the middle of the bar, and the fulcrum is located on the side of the bar opposite to the input


Applications:
In physics, a lever (from French lever, "to raise") is a rigid object that is used with an appropriate fulcrum or pivot point to multiply the mechanical force that can be applied to another object. This is also termed mechanical advantage, and is one example of the principle of moments. A lever is one of the six simple machines.


Items Required to make:
Popsicle sticks / Ice Cream Sticks
Cycle Spokes
Bamboo sticks
Sand / Small Bearing Balls
Card sheet

Fun Facts To Know:A mnemonic for remembering the three classes of levers is the word flex, where the letters f-l-e represent the fulcrum, the load, and the effort as being between the other two, in the first-class lever, the second-class lever, and the third-class lever respectively.