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PROPERTIES OF LIGHT
 

 

ENERGY TRANSFER - light is one of the ways in which energy is transferred.
1) conduction - molecule to molecule

2) convection - mass movement

3) radiation- radiant energy transferred as electromagnetic waves 

    light - light is the layman's term for visible radiant energy in the 400 to 700 nm wavelength region of the spectrum. In other words, it is the form of radiant energy (i.e. radiation) that animals can see. It is also the wavelengths of radiant energy that plants use in photosynthesis and for most other reactions that require light. 
     
LIGHT HAS FOUR PROPERTIES
1) quantity - the intensity or amount of light

2) quality - the wavelength or color of light

3) duration - determines the total amount of light energy received
                     total amount of light energy = quantity x # hours of light

4) photoperiod- the day length, or length of light in a 24 hour cycle, regardless of quantity. 
 
 

LIGHT CAN BE AFFECTED AS FOLLOWS
1) absorbed- when radiant energy (such as light) is absorbed it is converted primarily to heat energy.

re-radiation- heat energy is converted to radiant energy as long wavelengths in the infrared (IR)
                          region of the spectrum.

2) transmitted - when radiant energy (such as light) passes through an object unaffected, 
                         such as glass.

3) reflected or scattered - when radiant energy (such as light) is "bounced off" an object,
                                         such as a solid colored surface.

The color of an object is the color (as determined by wavelength) of light that is transmitted or reflected. In other words, your eyes see the color that is not absorbed.