OK, I may just be stupid, having just taken a long break from physics, but I'm having trouble with a problem about--you'll never guess--a bird.
It's flying--sorry, soaring--in a horizontal circular path. It's bank angle (relative to the horizontal) is estimated to be and the bird takes 13 s to complete one circle. How fast is the bird flying and what is the radius of the circle?
I would start by taking the normal force exerted on the bird by the air, at an angle of [MATH65^o[/tex] to the horizontal (90-25), and then finding the percentage of that force pushing the bird toward the center of the circle, but I don't know what to do after that.