# Emergency relief - Plane Vector

1. Feb 4, 2010

### Sirsh

As your aircraft moves in a northerly direction at a constant speed of 200 km h-1, it is
buffeted by winds of 80 km h-1 from the north-east.

Question 1 – What is the ground speed and direction of your aircraft while it is
being buffeted (Hit/pounded) by this wind?

Direction = Tan^-1 (80/200) = 21.8Degrees N-E
Speed = squareroot (200^2+80^2) = 215.4kmh^-1

My direction answer is wrong by a mear 0.3degrees, but, my speed answer is wrong. The answer in the text I'm studying out of says that the speed is 154kmh^-1, Except this is unlogical seeing that the wind is hitting the plane going in a north easternly direction therefore making the vector a addition vector (For example to show that the answer cannot be less then 200kmh^-1), it would seem that if the wind was coming southernly then it would slow down the plane.

Any help would be appreciated. Thanks.

2. Feb 4, 2010

### thebigstar25

if the question u have doesnt say that the wind is from north-east to south-west .. then ur answer is correct .. if it does then the answer in the book is right..