Question

A jetliner with an airspeed of 1000 kmlhr sets out on a 1500 km flight due south. To maintain
a southward direction, however, the plane must be pointed fifteen degrees west of south. Ifthe
flight takes 1 00 min, what is the wind velocity?

Answer 1

if the wind speed is s, set up the x- and y-components of the vectors:

first, work with velocity vectors only.
1500km in 100 min = 900km/hr

so, using the law of cosines,

s^2 = 1000^2 + 900^2 - 2(100)(90)cos30°
s = 1340 km/hr