C: Light and Optical Systems, section 3: light waves, spectrum, colours Flashcards
1
Q
wave model of light
A
light behaves like a wave in these ways:
- both travel out in all directions
- both are a form of energy
2
Q
visible light spectrum
A
red light wavelength is 700 nm
violet light is 400 nm
All visible light falls in between these values
700 nm = 0.000 000 7 m
3
Q
electromagnetic spectrum
A
- radio waves
- microwaves
- infrared waves
- visible light
- ultraviolet light
- x-rays
- gamma rays
4
Q
incandescent bulb
A
electrical energy runs through a filament
5
Q
fluorescent bulb
A
- glass tube with some gas inside such as mercury vapour that emits ultraviolet radiation when electricity passes through
- the inside of the tube is coated with phosphor (a white powder) which changes the ultraviolet radiation into visible light
6
Q
phosphorescence
A
glow in the dark for some time after being energized by light
7
Q
primary colours of light
A
red, green, blue
mixed together they form white light
8
Q
primary colours of light
A
red, green, blue
mixed together they form white light
9
Q
secondary colours of light
A
magenta (from red and blue), yellow (from red and green), cyan (from green and blue)
