waves - visible light Flashcards
what is specular reflection?
when all light rays are reflecting in a single direction. this takes place on smooth surfaces. it produced an image
e.g on a mirror
what is diffuse reflection?
on a rough surface where light rays are scattered. doesn’t produce an image
what does colour of an object depend on?
which wavelengths of light are reflected, transmitted or absorbed
how do coloured filters work?
absorb specific wavelengths and transmitting other wavelengths
what happens when white light shone into a red coloured filter?
filter absorbs all other colours of visible light apart from red. only red transmitted
(works same for other colours)
what can objects that transmit light be?
transparent (easily see through) or translucent (scatter light rays so cant see through clearly)
what are objects that are opaque?
cannot see through at all
why do white objects appear white?
they reflect all of the wavelengths of visible light equally
why do black objects appear black?
they absorb all the wavelengths of visible light
what happens when white light shone on red object?
all colours of white light absorbed apart from red, which is reflected. making object have red colour
(same for all coloured objects)
what happens when we combine a red object and red filter?
red filter absorbs all colours of white light apart from red which is transmitted. red light then reflects off red object making it appear red
what happens when we combine a red filter and green object?
red light transmits through red filter now green object absorbs red light but will appear black as it is reflecting no light at all
