Light Flashcards
What do solar panels do?
convert light energy to heat energy
Give an example of something that converts:
light energy to heat energy
light energy to chemical energy
solar panels
photosynthesis
what can light do?
work
what does crooke’s radiometer show?
that light can do work
what happens when the vanes move in crooke’s radiometer?
light energy is converted to kinetic energy
what do our eyes do?
detect light
give an example of 1. luminous objects
2. non-luminous objects
- Sun, fire, lightbulb
2. Table, chair, door
What is a luminous object?
An object that gives out light
what is a non-luminous object?
an object that reflects light (it does not give out light)
how does light travel?
in straight lines
do experiment to show light travels in straight lines
.
how are shadows formed?
When light rays are stopped by an object
When does a solar eclipse occur?
when the moon passes between the sun and the earth
What is the spectrum of light made up of?
7 colours
red, orange, yellow, green, blue, indigo and violet
richard, of, york, gave, battle, in, vain
what is dispersion?
the breaking up of white light into it’s spectrum of colours
how do we show that white light is made up of different colours?
we pass white light through a prism
when does a rainbow occur?
when light from the sun passes through raindrops
what is reflection?
when light bounces off a surface
what angle does light get reflected back at
the same angle as it struck
do the reflection experiment
.
what angle do the mirrors need to be at in a periscope if it is to work?
45*
What is a periscope?
An optical instrument that provides a view of an otherwise obstructed field using two mirrors at 45* angles reflecting light.
what is refraction?
the bending of light
how can refraction happen?
when light is passed through a solid or a liquid
what is seen to happen to light as it goes from the air into a glass block
change direction/bend
write out the refraction experiment
.
what is a focal point?
a point where light converges on or diperses from
what is a convex lens shaped like?
an oval
what is a concaved lens shaped like?
a rectangle with half an oval taken out of either side
what happens when light passes through a convex lens?
it comes together
what happens if you look at something through a convex lens?
it makes it look bigger
give an example of convex lenses
magnifying glass and glasses (for far away)
what happens when light passes through a concave lens?
it disperses
What happens when you look at something through a concave lens?
it appears smaller
give an example of a concaved lens
in reading glasses
What is light?
light is a form of energy
