Page 14 - mechanics

Chapter – 3 Concurrent forces in 3D

As A' lies in the xy plane, it can be resolved as in 2D case to a

component on x axis and another on y axis A' = Ax + Ay

Then by combining these equations, the vector A is

represented by the vector sum of its three rectangular

components,

A = Ax + Ay + Az (3.1)

Fig. 3.1 The resolution of a vector A into Cartesian components in 3D.

These components act in the direction of the coordinate axes.
To write the vector in numbers we need unit vectors as in 2D
case. We already defined i and j for x and y axes, respectively.
Now we present the unit vector k, which is a unit vector in the
z axis positive direction.

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