To maximize your cordless phone battery life, make sure to leave your phone off the base every once in a while until it is dead. Then leave it on the base until it is fully charged. You should leave your phone on the base for at least 24 hours to charge it fully. There is no need to avoid rechargeable batteries. They can save you significant amounts of money over time. Don't be scared off by the 'memory effect'.
In addition to being a great toy, the Slinky is an excellent device for creating and studying waves. A slinky can easily demonstrate the two basic types of waves, longitudinal and transverse. In a. longitudinal wave. the particles move parallel to the direction the wave is moving. In a. transverse wave. the particles move at right angles to the direction of wave travel.
Definition of Mechanical Waves. A mechanical wave is a wave that is a vibration in matter, transferring energy through a material. Not all waves are like this. For example, electromagnetic waves such as visible light are not mechanical because they can travel through the vacuum of space to reach us from the sun. Mechanical waves include water waves, sound waves, earthquake waves, and many more. Like all waves, those of the mechanical variety have peaks, or crests, and troughs. They also have a frequency, which is the number of waves that pass by per second, and a wavelength, which is the distance from one peak to the next, or one trough to the next.