Question

When a rectangle is constructed in order to add velocities, what represents the resultant of the velocities?

Answer 1

If side `AB` of a rectangle `ABCD` represents a velocity in one direction and `AD` - another, diagonal `AC` represents the resultant direction of movement.

Explanation:

Velocity is a vector with its direction and magnitude.

When two perpendicular forces act on an object, moving it simultaneously in two perpendicular directions from initial position `A` towards `B` and towards `D` with known magnitudes, the resultant vector of velocity is represented in direction and magnitude by diagonal `AC` of a rectangle built on vectors `AB` and `AD`.

Similar rule exists in a case of non-perpendicular directions of movement `AB` and `AD`, in which case `ABCD` is a parallelogram and the resultant vector of velocity will be represented by a diagonal `AC` of this parallelogram.