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iJamJL

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## Homework Statement

__Assume all speeds are constant.__

(a) A plane flies at speed vstill = 203 km/h in still air. Now, there is a wind blowing at speed vw = 77.6 km/h, with its direction at 30.4 degrees to the east of north. If the pilot wishes to fly due north with the wind blowing, find:

- θ, the angle between the direction the plane flies and due north.

- vp, the speed at which the plane will fly relative to the ground.

(b) A man walks up a stalled escalator in time tw = 89.3 s. If he stands on the moving escalator, he reaches to top in time tm = 26.4 s. Find twm, the time it would take him to reach the top if he walked up the moving escalator?

## Homework Equations

The only one I think that is possible is the Law of Cosines.

## The Attempt at a Solution

I have one vector going directly North because that is what we began with. Then there is a Northeast wind blowing, which is 30.4°. I put this vector's tail at the tail of the first vector going North. The resultant vector is then 141.8 if we use the Law of Cosines. As for the angle that the plane must fly, I'm at a loss, and have no idea. You don't necessarily have to tell me the answer, but where do I begin?

For the second question, I just have no idea at all.

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