Light and ColorWrite down the text in RED at least.

What is Light?Light is a type of energy

that travels as a waveLight is an

Electromagentic WaveIt has both an electric

field that travels up and down, and a magnetic field that travels back and forth

Light is a transverse wave (different from sound)

What is light?Light can travel

through empty space because it doesn’t need particles to crash together.

It can travel through air, glass, some plastics, and some liquids.

What is light?The speed of light is

unbelievably fast – about 300,000,000 meters per second!

Light is about 880,000 times faster than sound. That is why you see lightning much faster than you hear thunder.

How is light Produced?Incandescent light is

produced by heat.The filament inside a

bulb is made of a metal called tungsten. When tungsten gets hot, it changes the heat into light waves.

Electricity flows through the filament to make it hot

How is light produced?Fluorescent light is

produced when electrons of the gas atoms inside the bulb are energized and jump to the next valence level.

Not much heat is generated, so fluorescent bulbs use less electricity

How is light produced?LED stands for light

emitting diode.

LED light is produced when electrons move through a semiconductor diode, the e- drop to lower valence shells, and send out packets of light, or photons, when they drop.

How is light produced?Light from the sun is

produced by gamma rays exploding from fusion reactions inside the core of the sun.

All wavelengths of light in the EM spectrum are produced by the sun, but humans sense just light and heat.

Light carries energy.Biological energy

comes from plants using solar energy to conduct photosynthesis

The energy to create weather comes from solar energy

Light can be converted to electrical energy directly

Light carries informationLight travels through

tiny glass tubes, bouncing off the walls of the tube on the inside.

These bursts of light can carry information in the form of on-off signals

Light travels in a straight lineLight moves away

from a source in all directions at once – like a ripple in water.

The intensity of light decreases as it moves away from the source.

Light is part of the EM spectrum

Visible light is made of colorsThe visible light

from the sun is actually all of the wavelengths of light coming at once.

A prism (or water drops in the air) can split the white light into its colors

Sensing LightHumans can only

detect visible light and infrared light (as heat.)

Many insects, such as bees, can detect UV light

Sensing LightThe Hubble Telescope has instruments which

can detect all wavelengths of the EM spectrum.

The Orion constellation viewed in various wavelengths of the EM spectrum