Vectors in 2D
Grade 11 Physical Sciences
Vectors acting at an angle
3 Ways of describing the direction of
vectors
1. Bearings
2. Compass readings
3. X- and y-axes
1. Bearings
• With bearings, we use the
North as a reference line
(taken as 0°).
• We then measure an angle
clockwise from the reference
line to the vector in question.
• For example:
• Vector A in the diagram on the
left has a bearing of 30°
• Vector B has a bearing of 120°
2. Compass readings
• With compass readings, we use the
4 cardinal points i.e. North, South,
East and West or a combination of
these e.g. NE (North East) or even
combine these with angles.
• If the Cardinal points are used with
angles, we measure the angle from
the nearest cardinal point.
• For example:
• Vector A is 60o East of North or N 60° E
• Vector B is 20o west of South or S 20° W
3. x- and y-axis
• In this method, we measure the
angle with respect to the
negative or positive axis and
above or below.
• For example:
• Vector A is 30° above the positive
x-axis
• Vector B is 45° below the positive
x-axis.