Observing Light Flashcards
Light
Something that stimulates sight and makes things visible
Luminous
Something which gives off light:
The sun
Stars
Lightning
Non-Luminous
Something which reflects light, but doesn’t give it off:
The moon
Glass
Metal
Rectilinear Propagation
When light travels in straight lines
Shadows
a dark area or shape produced by a body coming between rays of light and a surface
Large light sources…..
Produces shadows with penumbras/larger penumbras
Small Light sources…..
Produce shadows with smaller penumbras or no penumbras
Light can travel through….
vacuums - space is a vacuum, and we can see stars and stuff, so light can travel through it
Light can not…
escape a black hole
Sound can’t travel through….
Vacuums
If a white light is shone onto a green ball, what colour would it be?
Green, because white is made up of RGB, and the green ball reflects green and absorbs red and blue
A green light it shone onto a red ball, what would the colour be?
Black, because the light is giving out green, but the red ball only reflects red and it absorbs the other colours, so it would appear black.
True or false, light refracts as it enters the prism
True
What is refraction?
The bending of light or change in direction of light
Dispersion is when…
Light spilts into colours of the spectrum
why do we see the flash of lightning before we hear thunder?
Light travels faster than sound
pinhole cameras
The image produced is shown upside-down
Where would you put a film in a pinhole camera?
Behind the screen
Umbra
total eclipse - the darkest part of a shadow
Penumbra
partial eclipse - the less dark ish part - usually grey or fuzzy
size and appearance, things that affect it
Distance between object and light-source
Distance between object and screen
Size of the object
Size of the screen
Emission
Light given out
eg. A light bulb - it gives out light, but light doesn’t go through it and out the other side
Transmission
When light passes through
eg. Glass - light goes through glass
Reflection
When light bounces off an object
