Check me- Speed(Arc Length) of Parametric Equations

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A ferris wheel has height = 100 ft and completes 1 revolution in 3 minutes at a constant speed. Compute the speed of a rider in the ferris wheel.

Ferris wheel = circle modeled by x= cos t ; y = sin t

radius = 50 ft; freq = 3^-1 min circle equation--> $ x= 50 \cos{3t} $ ; $ y= 50 \sin{3t} $

speed (s) $ = \sqrt{ (\frac{dx}{dt})^{2}+ (\frac{dy}{dt})^{2}}$

$ x'(t) = -150 \sin{3t} $

$ y'(t) = 150 \cos{3t} $

thus

s = $\sqrt{ 150^{2}\sin^{2}{3t}+ 150^{2}\cos^{2}{3t} }$

s = $\sqrt{ 150^{2}(\sin^{2}{3t}+ \cos^{2}{3t}) }$

s = $ 150 \sqrt{\sin^{2}{3t}+ \cos^{2}{3t} }$

s = 150 feet/min

Please verify my interpretation (feet/min) as well. Thank you

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$$v=r\omega=50ft\times\frac{2\pi}{3\times60}rad/s\approx0.531m/s\text{ or }104.52 ft/min$$


$$\omega=\frac{d\theta}{dt}=^*\frac{\Delta\theta}{\Delta t}\text{ *as it moves with constant velocity}$$