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Please help with a question on forming an equation!

Hey, i just need some help on this question:

The 'London Eye' can be considered to be a circular frame of radius 67.5m on th circumference of which are 'capsules' carrying a number of people round the circle. Take a co-ordinate system where O is the base of the circle and Oy is a diameter. At any time after starting off round the frame, the capsule will be at height h metres when it has rotated θ\theta degrees.

Give an expression for h in terms of θ\theta.

please give me some hints to get me started. Thank you!:smile:
Reply 1
Radius = 67.5m

If the capsule is below the horizontal, then using right angled trig:

67.5-67.5cosθ\theta=h

But this should hold for the entire circle because when θ>π2\theta>\frac{\pi}{2}, cosθcos\theta is negative.