Circular Motion with Newton's Laws

AI Thread Summary
The discussion focuses on analyzing the forces acting on a model airplane flying in a horizontal circle, specifically the tension, weight, and aerodynamic lift. The airplane has a mass of 7.50 kg and a speed of 35 m/s, with the control wire measuring 60.0 m. The aerodynamic lift acts at an angle of 20 degrees West of North, while the tension is at an angle of 20 degrees South of East. The participants are trying to derive the correct x and y scalar equations to solve for the tension, which is stated to be 12.8 N. The equations provided are based on the forces acting on the airplane, but there is confusion regarding the setup and orientation of the object in the problem.
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A model airplane of mass 7.50 with a speed 35m/s flies in a horizontal circle at the end of 60.0m control wire. Aerodynamic lift acts on the plane at an angle of 20 degrees West of North.

In the picture the book has the plane on the right. The weight is acting straight down, the tension is acting at angle of 20 degrees South of East and the aerodynamic lift is acting 20 degrees west of north.

Can someone set up the x and y scalar equations please. The answer is 12.8N. I have set it up 5 different ways and i can't seem to get the right answer. My teacher says always put the object on the left when doing these types of problems but it doesn't seem to work

Fx -Tcos20 - Fsin20 = mv^2/r
Fy -Tsin20 + Fcos20 - mg = 0 where T is the tension and F is the aerodynamic lift

Those are the equations based on the picture described.
 
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Fx -Tcos20 - Fsin20 = mv^2/r
Fy -Tsin20 + Fcos20 - mg = 0 where T is the tension and F is the aerodynamic lift

Those are the equations based on the picture described.
 
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