Topic 1 Flashcards
Define light
Light is a visible energy
Light is made of radiant energy
Light radiates from all source in all directions.
Light does not require matter to transfer between objects
Natural Light Source
Fire, Sun, Stars
Artificial Light Source
Light Bulb, LED
Incandescence
Electrical energy- Thermal energy (Heat)- Visible Light Energy
When a hot object emits light
Fluorescence
UV Light (Ultraviolet) - Energy absorbed (Mercury particles, Phosphor coating) particles - Visible Light Energy
Advantages - Less energy used / Energy efficient
Disadvantages - Very toxic if broken
Phosphorescence
Glow in the dark / Trampoline Park Socks
Absorb energy, store (not more light, the release)
Phosphorescence - exposure - removal of a source of radiation
Visible light - UV Light - Visible Light
Chemiluminescence
Chemical energy - Visible light energy
(E.g. Glow sticks / chemical)
When we break in half, we break the tube and mix the chemicals.
Chemiluminescence - chemical reaction, Glow sticks
Bioluminescence
Jellyfish light (glow) Fireflies
Chemical reaction inside bodies
Bioluminescence - special type of light produced in living creatures
Luminous (procedure) - emit light
Non- Luminous = does not emit light
When light strikes an object that is…
Transparent
All rays of light continue on a straight path.
When light strikes an object that is…
Translucent
Objects that allow some light through, but some light bends or bounces off.
When light strikes an object that is…
Opaque
Opaque - Objects that block all the light rays. Opaque materials cast shadows
Ray Model of Light
Light travels in straight lines called rays. You can use the ray model to predict where shadows will form and how large they will be. A ray diagram shows you how the distance from the light source affects the size of a shadow that an object makes.
First Principle of Light
Light is a form of energy, light can be transformed into other kinds of energy when it is absorbed by a surface.
