Light Flashcards
Energy
The ability to do work i.e move, uni of energy is he joule
Plants use of light
To make food (photosynthesis)
Humans use of light
Solar panels and crookes radiometer
Luminous
Objects that give off light are called luminous objects eg sun lightbulb candle
Non luminous
Objects that do not give off light and need light to bounce off them for us to see them are called non luminous eg a book my face a table
Light travels in straight lines
We can show this by blocking light from a bulb with card
Light does not travel around corners
Blocking lights lead to shadows
Solar eclipse
Occurs when the moon passes between the sun and the earth
Lunar eclipse
Occurs when the earth us between the sun and the monk, the moon is the earths shadow
Reflection of light
Occurs when it bounces off a surface
Regular reflection
The rays are reflected back at the same angle
Rough surface
A ball of tinfoil - irregular reflection
Concave or diverging mirrors
Telescopes, make up and shaving mirrors, can enlarge the image
Convex or converging mirrors
Side mirrors in cars, security mirrors in shops, small upright image with a wider field of vision
Refraction
The bending of light as it goes from one medium to another, eg- air to water
Light rays are refracted towards the denser material
