Waves 0707.11.6 Investigate the types and fundamental properties of waves. 0707.11.5 Create a graphic organizer to illustrate and describe the basic parts of a wave. 0707.11.6 Compare how transverse and longitudinal waves are produced and transmitted. SPI 0707.11.5 Compare and contrast the different parts of a wave. SPI 0707.11.6 Differentiate between transverse and longitudinal waves in terms of how they are produced and transmitted.

Waves Pre-test https://www.youtube.com/watch?v=0a5WyAjL1MM

Waves are everywhere in nature Sound waves visible light waves radio waves microwaves water waves stadium wave telephone waves earthquake waves waves on a string slinky waves Ultra-violent waves X-ray waves

Engineering Connection Waves are used for many reasons in our society: sonar, reading glasses, light bulbs, stereo equipment and lasers rely on either sound or light waves. For engineers to develop new (and already used) technology, they must understand how light and sound waves work and how to use them in new devices. https://www.youtube.com/watch?v=nLodC7Le8TM

Sonar Waves

Way a light bulb wave travels Take a “mental picture” you will see this again!

Wave A wave is a DISTURBANCE that travels through a medium from on location to another What in the world is a “medium?” Medium is MATTER The wave travels through some sort of matter

Vacuum Vacuum is space that is devoid of matter. The word stems from the Latin adjective vacuus for "vacant" or "void".

All waves can be categorized as Mechanical Travels through some sort of matter Example: sound travels through air, water, solids but cannot travel through a vacuum (an empty space) Electromagnetic Can travel through vacuum (empty spaces) Example: microwaves Light waves Radio waves

Slinky Wave When the slinky is stretched from end to end and is held at rest, it assumes a natural position known as the equilibrium or rest position. To introduce a wave here we must first create a disturbance. We must move a particle away from its rest position.

Slinky Wave This disturbance would look something like this

Pulsing One way to do this is to jerk the slinky forward the beginning of the slinky moves away from its equilibrium position and then back. the disturbance continues down the slinky. this disturbance that moves down the slinky is called a pulse. if we keep “pulsing” the slinky back and forth, we could get a repeating disturbance.

Another way to describe a wave is the way the disturbance travels 2 wave types are: (1) Longitudinal Waves (2) Transverse Waves

Longitudinal Waves The pulse is transferred through the medium of the slinky, but the slinky itself does not actually move. https://www.youtube.com/watch?v=7cDAYFTXq3E It just displaces from its rest position and then returns to it. So what really is being transferred? Energy

Longitudinal Waves https://www.youtube.com/watch?v=H0K2dvB-7WY Energy is being transferred. The metal of the slinky is the MEDIUM in that transfers the energy pulse of the wave. The medium ends up in the same place as it started … it just gets disturbed and then returns to it rest position. The same can be seen with a stadium wave https://www.youtube.com/watch?v=H0K2dvB-7WY

Transverse Waves In a transverse wave the pulse travels perpendicular to the disturbance. Transverse waves occur when we wiggle the slinky back and forth. https://www.youtube.com/watch?v=7cDAYFTXq3E

Transverse Waves http://hermes.ffn.ub.es/~albert/ones/wavemotion.html

Anatomy of a Wave Now we can begin to describe the anatomy of our waves. We will use a transverse wave to describe this since it is easier to see the pieces.

Anatomy of a Wave In our wave here the dashed line represents the equilibrium position. Once the medium is disturbed, it moves away from this position and then returns to it

Anatomy of a Wave crest The points A and F are called the CRESTS of the wave. This is the point where the wave exhibits the maximum amount of positive or upwards displacement

Anatomy of a Wave trough The points D and I are called the TROUGHS of the wave. These are the points where the wave exhibits its maximum negative or downward displacement.

Anatomy of a Wave Amplitude The distance between the dashed line and point A is called the Amplitude of the wave.\ This is the maximum displacement that the wave moves away from its equilibrium.

Anatomy of a Wave wavelength The distance between two consecutive similar points (in this case two crests) is called the wavelength. This is the length of the wave pulse. Between what other points is can a wavelength be measured?

Interesting Facts about Waves Waves in the ocean are mostly generated by the wind moving across the ocean surface. The "medium" is the substance or material that carries a mechanical wave. One of the most important things to remember about waves is that they transport energy, not matter. This makes them different from other phenomenon in physics. Many waves cannot be seen such as microwaves and radio waves. The tallest ocean wave ever recorded was 1,720 feet tall and occurred in Lituya Bay in Alaska

https://www.youtube.com/watch?v=w2s2fZr8sqQ