Vectors

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      A vector (PQ) is seen below. The length of a line segment is the magnitude of a vector. If the magnitude and direction of two vectors are equal, then they are equal.

      Vectors which can be translated from one position to another without any change in their magnitude or direction are called free vectors.

      The unit vector is a vector with a length or magnitude of one.

      The unit vector i is a vector with magnitude of one in the direction of the x-axis.

      The unit vector j is a vector with magnitude of one in the direction of the y-axis.

      When two vectors are added together, the reultant force of the two vectors produce the same effect as the two combined forces. In this instance, the vector R is called the reultant vector. This may be viewed below.