Introduction to Waves Essential Question: How are mechanical waves different and similar to electromagnetic waves? (S8P4a,d,f) Instructional Approach(s): The teacher should introduce the essential question and the standard that aligns to the essential question

Read This! Do not Copy WU 1/10 From the beach to home: Identifying waves Think and identify how many different waves were present. Imagine that your family has just returned home from a day at the beach. You had fun playing in the ocean under a hot sun. You put some cold pizza in the microwave for dinner, and you turn on the radio. Just then, the phone rings. It’s your friend calling to ask about homework

Use the PowerPoint to fill in the Waves graphic organizer as we discuss the characteristics of waves Instructional Approach(s): The teacher should give each student the Waves Notes sheet to use to record important information throughout the lesson

A disturbance that transfers (carries) energy without carrying matter What are Waves? A disturbance that transfers (carries) energy without carrying matter Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes

Types of Waves Mechanical Waves – need matter (or medium) to transfer energy A medium is the substance through which a wave can travel. Ex. Air; water; particles; strings; solids; liquids; gases Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes

Types of Waves Electromagnetic Waves – DO NOT NEED matter (or medium) to transfer energy They do not need a medium, but they can go through matter (medium), such as air, water, and glass Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes

How Waves Move Transverse (across) Energy causes the matter in the medium to move up and down or back and forth at right angles (perpendicular) to the direction the wave travels.

How Waves Move 2.Compressional (Longitudinal) (along) The matter in the medium moves forward and backward (parallel to) or along the same direction that the wave travels.

How waves move Transverse (Mechanical) Wave Examples: ocean waves, ripples in water, earthquakes, wave of people at a sporting event Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes. The teacher should use the link to provide examples of mechanical waves.

How waves move Compressional Wave (longitudinal) Ex. Sound waves A slinky is a good illustration of how a compressional wave moves Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes. Make sure that students are labeling the wave on the graphic organizer.

How waves move Electromagnetic Waves Electromagnetic waves move in a transverse waves . Examples: radiation, TV & radio waves, X-rays, microwaves, lasers, energy from the sun, visible light Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes. More to come on Electromagnetic waves…

Use the next slides and your Wave Diagram sheet to label and define the parts of a Transverse and Compressional wave.

Parts of a Transverse Wave The crest is the highest point on a wave. Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes. Make sure that students are labeling the wave on the graphic organizer.

Parts of a Transverse Wave The trough is the valley between two waves, is the lowest point. Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes. Make sure that students are labeling the wave on the graphic organizer.

Parts of a Transverse Wave The wavelength is the horizontal distance, either between the crests or troughs of two consecutive waves. Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes. Make sure that students are labeling the wave on the graphic organizer.

Parts of a Transverse Wave The amplitude is the peak (greatest) value (either positive or negative) of a wave. The distance from the undisturbed level to the trough or crest. Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes. Make sure that students are labeling the wave on the graphic organizer.

Parts of a Compressional Wave (Longitudinal) Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes. Make sure that students are labeling the wave on the graphic organizer. The compression is the part of the compressional wave where the particles are crowded together.

Parts of a Compressional Wave (Longitudinal) Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes. Make sure that students are labeling the wave on the graphic organizer. The rarefaction is the part of the compressional wave where the particles are spread apart.

Parts of a Compressional Wave (Longitudinal) Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes. Make sure that students are labeling the wave on the graphic organizer. The wavelength is the distance from compression to compression or rarefaction to rarefaction in a compressional wave.