11.1 What is Light

A) x-rays B) UV C) radio waves D) infrared light E) microwaves F) gamma rays G) visible light

A) baggage screening B) vitamin D C) Radar D) DVD player remote control E) telecommunication F) cancer treatment G) theatre/concert effects

Why is it useful to examine the universe using part of the electromagnetic spectrum other than visible light?

Objects in the universe emit many forms of electromagnet radiation besides visible light.

List some devices that you have used or plan to use today that involve electromagnetic waves.

Remote control, microwave oven, radio, cell phone, TV

Briefly describe how you could demonstrate that white light is composed of many different colours

Shine white light through a prism to produce a rainbow of colours.

From which electromagnetic waves must sunscreen protect the skin from.

Sunscreen protects from ultraviolet (UV) rays.

List the seven colours that Newton indentifies in the visible spectrum of white light.

The seven colours that Newton identified in the visible light spectrum were red, orange, yellow, green, blue, indigo and violet.

radiation

a method of energy transfer that does not require a medium; the energy travels at the speed of light

electromagnetic wave

a wave that had both electric and magnetic parts, does not require a medium, and travels at the speed of lighht

Medium

any physical substance through which energy can be transferred

visible light

electromagnetic waves that the human eye can detect

Order the electromagnetic waves from lowest to highest energy: infrared light, x-rays, red light, gamma rays, and mircowaves.

microwaves, infrared light, red light, x-rays, gamma rays

electromagnetic spectrum

the classification of electromagnetic waves by energy

visible spectrum

the continious sequence of colours that make up white light