Characteristics of Waves 8.P.3A.1 Construct explanations of the relationship between matter and energy based on the characteristics of mechanical and light waves

Waves Repeating disturbance or vibration that transfers or moves energy from place to place Created when a source of energy (force) causes vibrations Vibration is a repeated back-and-forth or up-and-down motion Waves carry energy through empty space or through a medium without transporting matter All waves can transmit energy through a medium Electromagnetic waves can transmit energy through empty space Medium is a material though which waves can travel. Solid, liquid, gas, plasma

Mechanical Waves Mechanical waves require the particles of the medium to vibrate in order for energy to be transferred Water Waves, Earthquake/seismic waves, sound waves, and waves that travel down a rope or spring Mechanical waves cannot be transferred or transmitted through empty space

Light Waves Electromagnetic waves Travel through matter or empty space Part of electromagnetic spectrum that is visible to the human eye

Movement of Waves Mechanical waves Matter particles vibrate by pushing together and moving apart parallel to the direction in which the wave travels are called “compressional” or “longitudinal waves” Place where wave is pushed together is called the “compression” Place that is moving apart is the rarefaction Sound/Seismic

Movement of Waves: Transverse Particles of matter in the medium vibrate by moving back and forth and perpendicular (Right Angles) to the direction the wave travels are transverse waves Highest point is the “crest” Lowest point is the “trough” Rope, water, slinky, string instrument Light waves are transverse that can travel without a medium

Properties of Waves 8.P.3A.2 Develop and Use Models to exemplify the basic properties of waves (including frequency, amplitude, wavelength and speed).

Frequency Measure of how many waves pass a certain point in a certain time. The higher the Frequency, the faster/the closer the waves are together. The higher the Frequency, the more energy carried by the waves Measured by hertz (Hz)

Wavelength Measure of the Distance from Crest A to Crest B Or Troughs Shorter Wavelengths are influence by Frequency Higher Frequency causes shorter the wavelength and greater the energy

Amplitude Measure of the distance of a line down the center of the wave to the crest or trough Middle Line is running on the plane the wave is moving on “Height” of the wave Greater the Force means Greater the amplitude and Energy carried In a Transverse Wave, Higher the Height, the Greater the Amplitude (Sound Waves) Greater Amplitude=Greater the Sounder (Light Waves) Greater Amplitude= Brighter the Light

Speed Distance a single wave travels in a certain time Speed determined by type of wave (Electromagnetic or Mechanical) and by the nature of the medium As a wave enters a different medium, the wave speed changes Each medium causes a different speed ALL FREQUENCIES of electromagnetic waves travel at the same speed in empty space How to calculate: Speed/Velocity equals the Frequency times the Wavelength V=f•λ