Hi friends, 1. The problem statement, all variables and given/known data Birds of prey rise up and down on thermals. A bird completes circle of radius 10m every 6s and rises vertically at a rate of 4.0 m/s. Assume uniform acceleration. Find a)speed of bird relative to ground b)magnitude of acceleration c)direction of birds acceleration d)angle between birds velocity vector and horizontal. 2. Relevant equations ar = v^2/r 3. The attempt at a solution I have got answers for a to c. a) 11.2 m/s b) 11 m/s^2 c) 0° But I cant really figure out how i can measure the angle. Could it be tan-1 = 4/11.2 = 19.65? God in the past few days I have been dreaming about angles. Please help me.