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I have a problem that seems easy to me to solve but I'm just not getting it. I'll give the problem and then what I've done so far.

A helicopter is moving horisontally to the right at a constant velocity. The weight of the helicopter is W = 51200N. The lift forceLgenerated by the rotating blade makes an angle of 21.0 degrees with respect to the vertical.

(a) What is the magnitude of the lift force?

(b) Determine the magnitude of the air resistanceRthat opposes the motion.

So I started out by drawing my free body diagram, making my component vector chart.

I have 3 forces acting on the helicopter;L,W, andR

For theLforce:

x component = Lcos21.0 degrees

y component = Lsin21.0 degrees

For theWforce:

x component = 0

y component = - W

For theRforce:

x component = - R

y component = 0

So when adding up my x components my equation looks like:

Net force of x = Lcos21.0 degrees - R

and my equation for the y component looks like:

Net force of y = Lsin21.0 degrees - W

But when solving for these equations I don't get the right answer. Where am I going wrong?

Thanks for any help provided.

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# Homework Help: Equilibrium at Constant Velocity

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