Properties and sources of light

What does the term ‘linear propagation’ mean?

• Light needs air to travel

• Light travels in straight lines

• Light can bounce off of things

• Light can bend

The entire range of energy, including visible light, propagated through waves is called

• The visible spectrum

• The invisible spectrum

• The electromagnetic spectrum

• Electrons

What colour the shortest wavelength of the visible light?

• Violet

• Green

• Red

• Indigo

Which statement is false?

• the greater the frequency, the shorter the wavelength

• Wavelength is measured in nanometers

• Blue light has more energy than red light

• The greater the wavelength, the shorter the frequency

What are the primary colours of light?

• Red, yellow, blue

• Cyan, magenta, yellow

• Red, blue, green

• white

What primary colours make up the secondary colour yellow?

• Red + green

• Red + blue

• Blue + green

• Trick question: yellow is a primary colour

Light is created when phosphor is exposed to UV radiation. This type of light is called:

• Chemiluminescence

• Phosphorescence

• Fluorescence

• Incandescence

This type of light is created when a compound is chemically activated by another compound:

• Bioluminescence

• Fluorescence

• Chemiluminescence

• triboluminescence

A lightbulb that has a tungsten filament gets really hot when electricity runs through it, and it glows bright orange. this type of light is called:

• LED

• Phosphorescence

• Fluorescence

• Incandescence

This type of light bulb is the most energy efficient because it gives off the least amount of heat and the most amount of light:

• Incandescent

• LED

• Fluorescent

• Phosphorescent