Light Flashcards
How do light rays pass through a convex lens (diagram)
What does “converge” mean?
To come together
What happens to light rays when they pass from a less dense to a more dense medium?
They move towards the normal
How do light rays pass through a concave lens?
What is meant by descibing a substance as a “medium”?
It allows light rays to travel through it
Describe the “normal”
A line at 90 degrees to the boundary between two substances acting as mediums
What does “diverge” mean
To move further apart
What is meant by an “opaque” substance?
A substance that doesn’t allow light to travel through it.
What is meant by a “transparent” substance?
A substance that lets light travel through it.
What is meant by a “translucent” substance?
A substance that lets some light through but makes the image fuzzy
Name the 3 primary colours in Science
Red
Green
Blue
Name the 3 basic secondary colours in Science
Yellow
Magenta
Cyan
Which 2 primary colours are mixed to make yellow?
Green and Red
What does “intensity” mean for light?
The level of light present
Which 2 primary colours are mixed to make magenta?
Red and Blue
Which 2 primary colours are mixed to make cyan?
Green and Blue
How can many other colours (e.g Orange..Pink..Brown etc) be made by mixing the primary colours?
By altering the intensity of one of the primary colours.
Orange can be made, for example, by lowering the intensity of Green light when mixing it with Red
How does light travel?
In straight lines called rays
Show how refraction occurs when a prism is used
The example shown is for a single wavelength of light
What colours make up the rainbow?
Show how white light refracts in a prism
Show how raindrops refract sunlight to show a rainbow
What is a colour filter?
A material that only allows certain colours to pass through it.
Why do we see certain substances as coloured?
The substance simple absorbs all the other colurs of the spectrum and reflects the colour we see.
No substance is truly coloured. It simply absorbs and reflects different wavelengths of white light
i) angle of incidence
ii) angle of reflection
iii) The normal
