Light Flashcards
(27 cards)
Light is a form of _____
energy
What is reflection?
When light bounces back from an object
What is incident ray?
The light-ray that strikes a surface
What is reflected ray?
Light-ray that reflects from a surface
What is normal?
A line that is at right angles to surface that incident ray strikes
What is angle of incidence?
Angle between incident ray and normal
What is angle of reflection?
Angle between reflected ray and normal
What is a plane mirror?
Mirror with flat surface
What is the law of reflection?
Angle of reflection is equal to the angle of incidence
What is refraction?
The bending of light
Why does the light refract?
Because it is entering a different medium and the speed changes
What happens if the light speeds up after it has entered the different medium?
It bends away from the normal
What happens if the light slows down after it has entered the different medium?
It bends towards the normal
What is a prism?
A glass/plastic block with a triangular-cross section
What is dispersion?
Splitting of white light into different colours
How is a rainbow formed?
By refraction, reflection and dispersion of a raindrop
If all colours are absorbed, what colour does the object appear?
Black
If all colours are reflected, what colour does the object appear?
White
What are the primary colours of light?
Red, green and blue
What are the secondary colours of light?
Cyan, yellow, magenta
Red+green =
yellow
Red+blue =
magenta
Green+blue =
cyan
Red+green+blue =
White light
