Q: An airplane is flying at 150 km/h on a heading of 070*. The wind is blowing at 40 km/h from a bearing of 130*. Find the ground speed (the magnitude of the ground velocity) of the airplane.
I am getting 134.54 km/h as the answer but the books answer is 110 km/h.
It would be great if someone can help me out! Thanks
I am getting 134.54 km/h as the answer but the books answer is 110 km/h.
It would be great if someone can help me out! Thanks
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With North being 0*
The wind is blowing FROM 130* so it is moving the plane 50* to the NW at 40km/h
The plane is flying 70* to the NE at 150 km/h
Solve the triangle for the missing side (and direction)
The exterior angle is 120* (50 + 70) ... the interior angle is 60
So the ground speed is:
c^2 = 150^2 + 40^2 -2(40)(150)cos60 by the law of cosines
c^2 = 150^2 + 1600 - 6000
c = 134.54 I think you are right
Yes...you should discuss it with your teacher
The wind is blowing FROM 130* so it is moving the plane 50* to the NW at 40km/h
The plane is flying 70* to the NE at 150 km/h
Solve the triangle for the missing side (and direction)
The exterior angle is 120* (50 + 70) ... the interior angle is 60
So the ground speed is:
c^2 = 150^2 + 40^2 -2(40)(150)cos60 by the law of cosines
c^2 = 150^2 + 1600 - 6000
c = 134.54 I think you are right
Yes...you should discuss it with your teacher