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

Wave is a repeating disturbance or vibration that transfers or moves energy, not matter, from place to place are created when a source of energy (force) causes a vibration A vibration is a repeated back-and-forth or up- and-down motion Waves carry energy through empty space (vacuum) or through a medium without transporting matter.

In one minute, how many different types of waves can you name? Record the names in your learner’s log. GO!

possible answers LightSoundSeismicOcean (water) Electromagnetic HandHeatHair Transverse Longitu dinalBrainMechanical SurfaceSPRadio Microwavestadium

A medium is a material through which waves can travel. It can be a solid, liquid, or gas. When waves travel through a medium, the particles of the medium are not carried along with the wave. When there is no medium, certain waves (electromagnetic) can travel through empty space

Mechanical waves require the particles of the medium to vibrate in order for energy to be transferred For example, water waves, earthquake/seismic waves, sound waves, and the waves that travel down a rope or spring are also mechanical waves. cannot be transferred or transmitted through empty space (vacuum)

Demonstrate mechanical waves Use the cup of water,tuning fork, and old school play telephone to demonstrate mechanical waves.

Light waves electromagnetic waves which are waves that can travel through matter or empty space where matter is not present are the only part of the electromagnetic spectrum that is visible to the human eye

Compressional or Longitudinal waves Mechanical waves in which the particles of matter in the medium vibrate by pushing together and moving apart parallel to the direction in which the wave travels

Examples of mechanical compressional/longitudinal waves might include sound waves and some seismic waves.

Transverse waves Mechanical waves in which the particles of matter in the medium vibrate by moving back and forth and perpendicular (at right angles) to the direction the wave travels

The highest point of a transverse wave is the crest and the lowest point is called a trough

Examples of mechanical transverse waves might include some waves in a slinky spring, waves on a rope, strings in a musical instrument, and some seismic waves

Light waves are transverse waves that can travel without a medium through empty space

Let’s make waves! Demonstrate a stadium wave as a class Demonstrate a transverse wave as a class Demonstrate a longitudinal wave as a class

Written Review Complete the Venn diagram for mechanical waves and light waves using your notes and the video.

Answers Carry energy Mechanical Requires a medium Can’t travel in empty space (vacuum) Low speed Compressional Longitudinal Can travel through opaque objects Water waves Seismic sound Carry energy Light (electromagnetic) No medium required Can travel in empty space (vacuum) High speed Transverse Visible to human eye Can’t travel through opaque objects