Unit 3 Waves and Light Lesson 1 Waves

Unit 3 Waves and Light Lesson 1 Waves • A wave is the transmission of energy through matter or empty space. • There are several kinds of waves: light, sound, ocean, micro, and radio • Waves travel from a source and move away from that source • Energy transmits through materials through vibrations. Vibrations are a back and forth motion that constantly repeats within a set of objects (particles). For instance, a vibrating particle passes its energy to a second nearby particle causing it to vibrate like itself.

Unit 3 Waves and Light Lesson 1 Waves • When you hear the word wave, what do you think of?

Unit 3 Waves and Light Lesson 1 Waves • Classification of Waves: 1. Mechanical waves: waves that need to travel through a medium (solids, liquids, or gases) - examples would be sound (does not travel through a vacuum) and ocean waves 2. Electromagnetic waves: waves that do not need a medium in order to transmit - examples are radiation, UV light, x-rays, gamma rays, microwaves, infrared waves, and visible light

Unit 3 Waves and Light Lesson 1 Waves • Types of Waves 1. Transverse waves – waves that have particles that move up and down in a perpendicular (across) direction. -parts: crest (highest point) and trough (lowest point) -example: electromagnetic waves

Unit 3 Waves and Light Lesson 1 Waves • Types of Waves (con’t) 2. Longitudinal waves – wave where particles move back and forth along the direction of the wave within a given medium - parts: compression (crunched together) and rarefaction (spread apart) - examples: sound waves

Unit 3 Waves and Light Lesson 1 Waves • Types of Waves (con’t) 3. Surface waves = move in circles: particles move forward at the crest and backwards at the trough -parts= transverse + longitudinal waves