SOLUTION: Ive been struggling for days to get the answer to this question: A ferris wheel has a raidus of 20 m. Passengers get on halfway up on the right side. The direction of rotation is

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Question 639842: Ive been struggling for days to get the answer to this question:
A ferris wheel has a raidus of 20 m. Passengers get on halfway up on the right side. The direction of rotation is counter clockwise. The bottom of the ferris wheel is 2 m above ground. It rotates every 36 seconds.
I had to draw it and I think that is right, but I am not sure how to determine a sine function that expresses my height. when h is a function of elapsed time t.
I got h= -20sinpie/18(t)+22
And I am lost when they ask to determine my height above the ground after 15 seconds algebraically
and the the nearest tenth when my height is 38 m above the ground algebraically.
Please help. I can't do that following questions because I think my equation and graph is wrong! Thank you
Must be algebraically though thank you
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
A ferris wheel has a raidus of 20 m. Passengers get on halfway up on the right side. The direction of rotation is counter clockwise. The bottom of the ferris wheel is 2 m above ground. It rotates every 36 seconds. Determine height above the ground after 15 seconds algebraically. Determine seconds to the nearest tenth when height is 38 m above the ground algebraically.
**
let t=seconds after wheel starts to rotate.
let h=meters above ground after wheel starts to rotate
..
The formula I got: h(t)=20sin(πt/18)+22
This is close to the formula you got, except I left the negative sign out since passengers start to rise after the wheel starts going counter-clockwise.
..
After 15 seconds:
h=20sin(15π/18)+22
=20sin(5π/6)+22
=20*(1/2)+22
=32 m
..
When h=38 m
38=20sin(πt/18)+22
38-22=20sin(πt/18)
20sin(πt/18)=16
sin(πt/18)=16/20=4/5=.8
arcsin(.8)=0.927
πt/18=0.927 (radians)
t=(.927*18)/π≈5.31
..
height above the ground after 15 seconds≈38 m
seconds elapsed when height is 38 m above ground≈5.3 seconds