FORCES AND VECTORS
Terminology:
Scalar  a quantity that describes MAGNITUDE or size ie temperature, time, volume, mass
Vector:
 a quantity that has both MAGNITUDE and DIRECTION ie displacement (distance moved or traveled) or velocity,
weight
 represented as a DIRECTED line segment with an arrowhead that indicates the direction
 the MAGNITUDE of the vector, |v| is represented by the LENGTH of the directed line segment DRAWN TO
SCALE {when drawing vectors, an appropriate scale is required and must be written on the diagram}
 TAIL of the vector, represents the origin or start of the vector
head
 HEAD of the vector, is the tip or arrowhead
v
 Vectors are written as: q , or -u or AB
tail
 Vector AB has magnitude |AB|, it is written as an absolute value because magnitude is always positive
B
A
AB
Equivalent Vectors  (also known as equal vectors) have the SAME magnitude and SAME direction, but may have
different positions
u
v
Opposite Vectors have the SAME magnitude but are in the OPPOSITE direction ie 9 N N30°E is opposite to 9 N S30°W
d
b
Parallel Vectors have the SAME direction, but DIFFERENT magnitude ie 9 N N30°E is parallel to 12 N N30°E
e
d
RECALL: Directions of Vectors
True Bearing (or Bearings) an angle measured clockwise from North and expressed as a 3-digit number e.g. 078°, 345°
Conventional Bearing or Quadrant Bearing (direction) an angle between 0° and 90° measured east or west of the northsouth line e.g. N450E, S720W.
Vectors can also be described directionally by the use of the words UP or DOWN, LEFT or RIGHT.