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An airplane is headed on a bearing of 130 degrees at an airspeed of 261 km per hr. A 58 km per hr wind is blowing from a direction of 217 degrees. Find the groundspeed and resulting bearing of the plane. |
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Answer» From thediagram attached Angle ABC =217 – 130 = 87
Using thecosine rule
b² = a²+ c²– 2AC Cos B b² = 58² +261² – 2x58x261 Cos 87
= 69900.4766 b = 264.4km/h
Gettingangle BAC using Sine rule
a/Sin A = b/Sin B 58/Sin A =264.4/ Sin 87 Sin A =(58XSin87)/264.4 = 0.219
A = 12.7
BEARING angle= 130 – 12.7 = 117.3
GROUND speed= 264.4 km/h Bearing =117.3 |
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