luminous object: something that produces its own l Moon is bright only because it ects the Sun’s light. Therefore, the is NOT luminous.
Mar 31, 2015
luminous object: something that produces its own light
The Moon is bright only because it reflects the Sun’s light. Therefore, theMoon is NOT luminous.
1. Incandescence: light that is emitted from a very hot object
sodium vapour lamps
a) electric discharge
neon lights
2. Luminescence: light that is generated without heating the object
- types:
LEDs(light-emitting diodes)
b) chemiluminescence: light that is produced by a chemical reaction without a rise in temperature
c) bioluminescence: light that is produced by a biochemical reaction in a living organism
and mercury
d) fluorescence: light that is emitted during exposure of the source to ultraviolet (UV) light
compact fluorescent light (CFL) bulbtubular fluorescent light bulb
Uses of Fluorescence
forensic science
black light theatre
fluorescent fish
money
e) phosphorescence: light that is emitted due to exposure of the source to UV light, and that continues to be emitted for some time in the absence of the UV light
Reflection diagram
Characteristics of Images
Size bigger or smallerAttitude upright or invertedLocation closer or fartherType real or virtual
Curved mirrors
Lens and mirror equation
Refraction diagram
Index of refraction
n =c/vC-speed of light in a vacuum 3.0 x 10 8m/s
V-speed of light in medium
Internal reflection
Lenses
Diverging lens
The eye
Colour Theory