physics flashcards
(45 cards)
how does light travel?
from source light travels in straight lines, light travels as traverse waves.and it travels much faster than sound.
what can/cannot light travel through
light can travel through transparent objects, can travel a little through translucent objects and not through opaque objects
how are shadows formed
shadows are formed when a opaque objects absorbs and reflects light traveling through it meaning the part behind the objects gets no light causing a shadow
what colours absorb and reflect light
white reflects most light
black absorbs most light
what happens to light depending on the surface
if the surface is rough the light rays will scatter and if its smooth then it will stay together and reflect evenly
what is it called when the light is evenly rejected on a smooth surface
Specular refection
what is refraction
when light hits something transparent and changes the speed and direction
what do converging lenses do
make rays of light come together
what is the focal point
where parallel rays of light are brought together by the lens
what is the focal length
the distance of a focal point to the centre of the lens
give three examples of when eyes are used
cameras microscope and telescope
what are rod cells
road cells are in our retainers detect faint light but not colours
what are cone cells
they detect primary colours of red blue and green
what is white light
white light is a mixture of colours which can be spilt up using a prism to give a spectrum of seven colours
red ,orange, yellow,green,blue,indigo,violet
what is it called hone you split up colours into a spectrum
dispersion
how can we see certain colours
because certain colours reflect the colour they look and absorb the rest
what are filters ad what do they do
they are used to make coloured light.they transmit one of the colours in white light and let the other colours through
what is static electricity
it is a electric charge that builds up on the surface of an insulator.this is hard to flow away from the insulator
what is electric charge
is produced when two different types of insulators rub together
what’re the two types of electric charge
positive charge
negative charge
why does electric charge when gaining electrons become negative
because electrons move and they are negative meaning when electrons are passed they add on to the insulator with more negative charge
what charges attract each other
positive charge and negative charge
what charges repel each other
negative charge+negative charge
positive charge+positive charge
do protons move
no
