INNOVATIONS IN LIGHT AND SOUND

amplifiers

makes quiet sounds loud

-a small sound wave is converted into an electrical signal

-uses electrical power to boost the height/power of this signal

-the boosted power is sent to a speaker, which creates a much louder sound wave

soundproofing

stops sounds from entering and leaving the room

-sound travels as a vibrations

-soft, irregular, and dense material

-absorbs the sound wave's energy, trapping the vibration and converting it into tiny amounts of heat

LEDS

a highly efficient and durable source of light

-if is a semiconductor

-when electricity passes through it, it directly excites electrons, which releases their energy as EFFICIENT LIGHT WAVES of a specific color

-creates light without needing to create a lot of heat

lasers

a single, powerful, and highly focused beam of light

-produces coherent light, meaning all the light waves are the same color and travel perfectly in sync in one direction

-creates a single, intense beam that can be precisely aimed

holograms

a three-dimensional image made of light

-made by splitting a laser beam. one part hits the object, the other hits the film directly

-the two beams meet and interfere with each other

traditional bulb (incandescent)

works by heating a wire until it glows, wasting >90% of its energy as heat