why is d 16

578 Trigonometry - Functions and Graphs Lesson #10: Modelling Sinusoidal Functions 2. A Ferris Wheel ride can be represented by a sinusoidal function. A Ferris Wheel at Westworld Theme Park has a radius of 15 m and travels at a rate of six revolutions per minute in a clockwise rotation. Ling and Lucy board the ride at the bottom chair from a platform one metre above the ground. a) Sketch three cycles of a sinusoidal graph to represent the height Ling and Lucy are above the ground, in metres, as a function of time, in seconds. 31 15 3 cycles t 30. sec seconds 1min b) Determine the equation of the graph in the form h(t) = a cos [b(t - c)] + d. a = max -min 31- 2 2= 15 b= 271- 2TL_ TL P 10 C = 5 d = 1 alt ) = 15cos (TL (t-5) ) + 1 c) If the Ferris Wheel does not stop, determine the height Ling and Lucy are above the ground after 28 seconds. Give answer to the nearest tenth of metre. h( 20) = 1scos( $(28-5)) + 1 d) How long after the wheel starts rotating do Ling and Lucy first reach 12 metres from the ground? Give answer to the nearest tenth of a second. e) How long does it take from the first time Ling and Lucy reach 12 metres until they next reach 12 metres from the ground? Give answer to the nearest second. Copyright @ by Absolute Value Publications. This book is NOT covered by the Cancopy agreement