Week Three Summary of Science Lesson 1

Hey guys!
This week lesson we learned about sound of wave. First of all before I start to tell about sound of wave, let's discuss about waves.

Wave are vibrations that transfer energy from one place to another without matter being involved. Based on the propagation medium, the waves are grouped into two, namely mechanical waves and electromagnetic waves. Mechanical wave is a wave that requires a medium in the propagation. Propagate through a material medium (solid, liquid or gas). Examples include mechanical waves:
- Sound waves
- Water surface waves
- Waves on string

Electromagnetic waves are waves that do not require the propagation medium. 
Example:
-Light
-Radio waves
- TV waves
- X-rays
- Gamma rays

Properties of waves:

There are many properties of waves which are amplitude, frequency, period, wavelength, speed and phrase. Frequency is the number of vibrations in one second measured in Hertz (Hz). 

Period is the time needed to make one vibration. Frequency and period are different but, it related quantities. Frequency refers to how something happens. Period refers to the time it takes something to happen. 

The formula for frequency

f= number of vibrations/(one) second

The equation for period

T= 1/f

Categories of Waves:

Waves come in many shapes and forms. There are two basic types of waves, which are,

Longitudinal Waves and Transverse Waves.

For transverse waves the displacement of the medium is perpendicular to the direction of propagation of the wave. The examples of transverse waves are: 

- Water waves

- Vibrating guitar string

- Radio waves

- X-rays

Crest - top of wave

Through - bottom of wave

Amplitude - distance form rest position to top or bottom of wavelength (l)

Wavelength - distance from crest to crest or trough to trough

Undisturbed/Rest position - the wave is at equilibrium, that is the wave is not moving up or down.

Longitudinal waves the displacement of the medium is parallel to the propagation of the wave. The examples of longitudinal waves ware:

- Sound waves in water

- Vibrations in gases

- Ultra sound

Continue to Week Three Summary of Science Lesson 2