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Vector Direction - help5

Vector quantities are quantities like displacement and force (to name just two) that are fully described by expressing a magnitude (or numerical value) and a direction. Agreed-upon conventions are required to express the direction of any vector that is not aligned with the traditional east-west-north-south compass directions. The counter-clockwise from east convention expresses the direction of a vector as the counter-clockwise angle of rotation that the vector makes with due east.

There are three similar versions of this question. Each includes a vector that lies along one of the axes. The task involves determining the direction of the vector using the counter-clockwise form East convention.

Questions 13-15:

Use the protractor to determine the direction of the given vector. Express your answer using the counter-clockwise (CCW) from East convention. (The angle measure is a multiple of 15 degrees.)

The Counter-Clockwise (CCW) Convention is an agreed-upon method of expressing the direction of a vector as being equal to some counter-clockwise angle of rotation from due East. According to this convention, East is assigned the direction 0°. A vector that starts at East and is rotated in the counter-clockwise direction by a 90° angle would point North. Thus, North is assigned the direction of 90°. By similar reasoning, West is 180° and South is 270°. Vectors lying between these compass directions will have CCW directions that are in between these angle values. For instance, a third quadrant vector lying between West and South would have a CCW direction that is between 180° (for West) and 270° (for South).

In this question, the vector lies along one of the axes. So don't be fooled into making the question harder than it is. The answer is either 90°, 180° or 270°. You can do it!

Try this link to The Physics Classroom Tutorial for more help with vector direction:

Vector Direction