A Level Maths Notes: M1 – Finding the Velocity Vector Given Speed and Direction
We can be given a velocity in more than one way. One way is to be given a speed together with a bearing. The velocity can be found using trigonometry.
Example: A car is travelling at 50m/s on a bearing of 240 degrees. Find the velocity.
The vertical componenent of the velocity is![]()
The horizontal component of the velocity is![]()
The velocity is![]()
We may be given the direction as a vector. If we are told the
speed is 8m/s in direction
which
has magnitude
then
we can compare the speed with the length of this vector. It is
times
bigger, so we can multiply
by
1.6 to get the velocity vector. It is![]()