WAVES part I

(Note: light and ANY E&M wave are synonymous in physics. If you mean just that limited portion of the spectrum which humans can see, you MUST say “visible light”. The Big Picture:

Types of Electromagnetic Radiation (Recall: In physics "light " and any E&M wave are synonymous. If you mean just that limited portion of the spectrum which humans can see, you must say “visible light”. Remember: light can travel through the vacuum of space. Thus the planet receives the necessary sun - light, where “light ” means infrared, ultraviolet, microwaves, etc. radio & television waves microwaves infrared radiation visible light ultraviolet radiation x-rays gamma rays Remember: “ R O Y G B I V “ 700 nm or 7000 C 600 nm or 6000 C 500 nm or 5000 C 400 nm or 4000 C decreasing increasing wavelength frequency (Hertz) (meters) & energy (Joules)  E = h

TRANSVERSE WAVES Transverse means perpendicular, so wave motion must be  to the direction the wave is moving. Thus, the coils in a slinky would have to move either side-to-side or up-&-down to create a transverse wave.

LONGITUDINAL WAVES Longitudinal means parallel, so wave motion must be  to the direction the wave is moving. Thus, the coils in a slinky would have to be bunched up & then released to create a transverse wave. Note: longitudinal waves are also called pressure or compression waves because of how they are formed.

compressions rarefactions LONGITUDINAL WAVES continued Compression and rarefaction are vocabulary words. Also, remember that sound is a longitudinal wave. In fact, the left part of the picture below represents a speaker producing sound waves in the air as it vibrates.