# Thread: find the velocity vector and speed of plane relative to the ground

1. ## find the velocity vector and speed of plane relative to the ground

Alright, this is very confusing.

Q. Suppose an airplane is pointing due west and flying with an airspeed of 500mph, and that there is a 200mph wind out of the south west. Find the velocity vector of the plane relative to the ground. What is the speed of the plane relative to the ground?

2. The velocity relative to ground is the sum of the velocities:
500mph pointing west
200mph pointing north east (from south west)

3. so both are positive velocities right?

4. so it's just 700 mph?

5. Originally Posted by Taurus3
so it's just 700 mph?
No, the directions matter.
Do you know the rules for vector addition?
You need to use trig.

6. Originally Posted by snowtea
The velocity relative to ground is the sum of the velocities:
500mph pointing west
200mph pointing north east (from south west)
@OP: I have highlighted a key word .... (Velocity is very different to speed ....)