MT 6 LT 1 Mechanical Waves What are waves?
Background Knowledge: Waves What are some examples of waves? Why are waves important?
What causes waves? Waves are created when a source of Energy causes a medium to vibrate. WAVES NEED ENERGY TO MOVE A vibration is a repeated back and forth or up and down motion.
What are the different types of Wave? Mechanical Waves Sound Waves Electromagnetic Waves
This LT will focus on Mechanical Waves
What are mechanical waves? Definition: A disturbance that transfers energy from place to place. They need a source of energy to produce it
How are waves & energy related? A wave transports energy along a Medium without transporting matter.
Mediums & Waves What do mechanical waves move through? A medium Mechanical waves require a medium in order to travel from one place to another Can be gas, liquid, or solid. Waves in different mediums travel at different speeds.
Mediums & Waves What do mechanical waves move through? Mechanical Waves do NOT move the medium from one place to another Note that Not all waves require a medium to travel. Example: Light from the sun travels through empty space.
What determines the speed of a Mechanical Wave? The speed of a wave is determined by its: Wavelength x Frequency
What are the different types of Mechanical Waves?
What are the different types of Mechanical Waves? Waves are classified according to how they move. 3 types of Waves: Transverse Wave Longitudinal Wave Surface Wave
What is a Transverse Wave? A wave that travels in the opposite direction (perpendicular) to the medium in which it is traveling through Transverse means across.
Basic Properties of Transverse Waves (What are the parts of a Transverse Wave?) Crest Trough Amplitude Energy Wavelength
Basic Properties of Transverse Waves (What are the parts of a Transverse Wave?) Crest The highest point of the wave above the rest position Trough The lowest point below the rest position
Transverse Wave: Amplitude Amplitude is the distance from the rest to crest or rest to trough. The farther a medium moves as it vibrates, the larger the amplitude. Rest
Transverse Wave: Amplitude The Amplitude tells us the amount of energy being transported. High Energy = High Amplitude Low Energy = Low Amplitude.
Transverse: Wavelength A wave travels a certain distance before it repeats. When it repeats, it is knows as the Wavelength The wavelength is the distance between 2 corresponding (same/related) parts of a wave . Measured from crest to crest or trough to trough.
Wave Height The distance from one crest to one trough (trough to crest too)
Draw a Transverse Wave and label: crest & trough
Properties of Longitudinal/Compressional Waves
Longitudinal Wave The vibration of the medium is the same direction (parallel) to the direction in which the wave travels. Example: Slinky
Longitudinal Wave Rarefactions Compressions: The parts where the coils are close together Rarefactions the parts where the coils are spread out
What is a Surface Wave?
Surface Waves A wave that travels along a surface separating two media