Certain substances will split a ray of light into two slightly different paths by polarisation. If a crystal transmits light without splitting it in this way when the light is incident on the crystal in only one direction then the crystal is said to be uniaxial. If light is transmitted when it is incident in either of two directions then the crystal is said to be biaxial.
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Biaxial joints allow for movement in two planes or axes. A common example of a biaxial joint is the wrist, which allow for movement side to side, and also allows for movement up and down. It can be difficult to determine whether a joint is biaxial or multiaxial, because when the biaxial joint moves in both directions at the same time, it appears to have the multiaxial quality of being able to move in any plane or axes.
biaxial joint
humeroradial joint
what ever you want it to mean
That's kind of vague, but I'm thinking you mean a crystal.
The difference between a uniaxial and a biaxial crystal is that a uniaxial crystal has 1 optic axes, while a biaxial crystal has 2 optic axes.
A bisectrix is the line bisecting the angle between the optic axes of a biaxial crystal.
yes
Yes
Biaxial joints allow for movement in two planes or axes. A common example of a biaxial joint is the wrist, which allow for movement side to side, and also allows for movement up and down. It can be difficult to determine whether a joint is biaxial or multiaxial, because when the biaxial joint moves in both directions at the same time, it appears to have the multiaxial quality of being able to move in any plane or axes.
yes
There are two types uniaxial or biaxial.
biaxial joint
Biaxial cable consists of two side-by-side coaxial cables held together by an outer insulating jacket.
a crystal structure is a turtle in disguise
yes
a crystal structure is a turtle in disguise