Dextrorotatory and dextrorotation are terms used in chemistry to describe the direction in which a substance rotates plane-polarized light. When a substance is said to be dextrorotatory, it means that it rotates plane-polarized light to the right or clockwise direction, whereas when it is levorotatory, it rotates plane-polarized light to the left or counterclockwise direction.

The terms "dextrorotatory" and "levorotatory" come from the Latin words "dexter" meaning "right" and "lævus" meaning...

The two vectors (say A and B) of different magnitudes cannot be combined to give zero resultant since minimum value of combination is ІA-BІ which is not zero if AB.

The three vectors A, B and C of different magnitudes can be zero such that they form a closed triangle, then,

      A+B+C=0

or, C=-(A+B)

Hence, the sum of three vectors may be zero if vector sum of any two vectors is equal and opposite to the third vector.

Note: The vectors can give this result only if...