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Woolyabyss
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Homework Statement
An aircraft flew due east fro P to Q at u1 km/h.Wind speed from south west was v km/h.On the return journey from Q to P,due west, the aircraft's speed was u2 km/h, the wind velocity being unchanged.If the speed of the aircraft in still air was x km/h, x>v,show by resolving the perpendicular to PQ.or otherwise,that
u1 - u2 = v√2
Homework Equations
3. The Attempt at a Solution [/b/
Can somebody help me with this?I think I made a simple mistake.
vpw = (xcosa)i - (xsina)j
vw = (v√2/2)i + (v√2/2)j
vp = (xcosa + v√2/2)i +(xsina + v√2/2)
since the j component must be zero sina = 2v/2x .... cosa =√(4x^2 -2v^2)/2x
vp =x√(4x^2 -2v^2)/2x + v√2/2 = (v√2 + √(4x^2 -2v^2))/2 = u1
return journey
since the plane is traveling in the opposite direction
vpw = (-xcosa)i - (xsina)j
vp = (-xcosa + v√2/2)i +(-xsina + v√2/2)j
since j is zero cosa =√(4x^2-2v^2)/2x
u2=vp= (v√2 - √4x^2 -2v^2)/2 i
u1 - u2 = (√(4x^2 - 2v^2) +√(2v^2))/2 - (√(4x^2 -2v^2) - √(2v^2))/2
If I simplify it doesn't work out.Should I have multiplied u2 by minus 1 since its going in the minus i direction?