Come up with a sine equation for the following word problem.

[supernova1203]

niagra falls skywheel, a ferris wheel has a diameter of 50.5 m and rotates 1 revolution in 2 minutes. the lowest point on the wheel is 2.5 m from the ground.

This is the equation i have come up with, please tell me if this is right or not, and if it is not please come up with your own equation and show me how you did it.

the base equation is y=aSin(k(x-d))+c

max height = 50.5m

min height = 2.5m

period = 2 mins or 120 seconds

vertical shift = max height + min height/2

=50.5+2.5/2

=53/2

= 26.5 m

vertical stretch = maxpoint -midpoint
or amplitude
=50.5-26.5

=24m

since there is no horizontal shift

y=asin(k(x-d))+c

y=24sin(2x)+26.5

or y=24sin(120x)+26.5 depending on how you look at the period in seconds or minutes.

[LCKurtz]

You never stated what equation you are trying to find. Since this is a rotating wheel, wouldn't the variable t = time be involved? And if you are trying to keep track of a moving point on the wheel, wouldn't you need both x and y coordinates in terms of time? And wouldn't you normally use radian measure?

What is the exact statement of your problem?

[supernova1203]

um.. sine equation..sine function

y=asin(k(x-d))+c

that kind of equation

your supposed to find the vertical stretch = a

k=period/horizontal stretch/compression

d=horizontal shift

c=vertical shift

[LCKurtz]

You never stated what equation you are trying to find. Since this is a rotating wheel, wouldn't the variable t = time be involved? And if you are trying to keep track of a moving point on the wheel, wouldn't you need both x and y coordinates in terms of time? And wouldn't you normally use radian measure?

What is the exact statement of your problem?

um.. sine equation..sine function

y=asin(k(x-d))+c

that kind of equation

your supposed to find the vertical stretch = a

k=period/horizontal stretch/compression

d=horizontal shift

c=vertical shift

Look, a ferris wheel is circular. I could just give you the equation of its circle which would have the form x2+(y-a)2 = r2. That would be the equation of the ferris wheel if you put in the correct numbers for a and r.

I assume that isn't the equation you want. But you haven't told us what equation you want. It apparently involves motion but you haven't addressed any of the questions in my last post. It might help if you would give exactly, word for word, the statement of the problem.

[HallsofIvy]

As LCKurtz has said, no equation makes sense until you say exactly what your variables represent. I think you want to say something like "y is the height above the ground of a specific point on the ferris wheel and x is the time in seconds." Further you need to specify which specific point, and it looks like you are taking y to be the height of one of the two points on the wheel that is at the same height as the center of the ferris wheel when t= 0.

[supernova1203]

Look, a ferris wheel is circular. I could just give you the equation of its circle which would have the form x2+(y-a)2 = r2. That would be the equation of the ferris wheel if you put in the correct numbers for a and r.

I assume that isn't the equation you want. But you haven't told us what equation you want. It apparently involves motion but you haven't addressed any of the questions in my last post. It might help if you would give exactly, word for word, the statement of the problem.


hm... ok ill show you exactly what the question says in the attachment

[supernova1203]

heres the entire question :) hope it helps

[sjb-2812]

niagra falls skywheel, a ferris wheel has a diameter of 50.5 m and rotates 1 revolution in 2 minutes. the lowest point on the wheel is 2.5 m from the ground.

This is the equation i have come up with, please tell me if this is right or not, and if it is not please come up with your own equation and show me how you did it.

the base equation is y=aSin(k(x-d))+c

max height = 50.5m.

Even taking everything everyone else has said, are you sure about this?

[LCKurtz]

OK, at least now we know what the question was. I will get you started with a picture:

http://math.asu.edu/~kurtz/pix/ferriswheel.jpg

I have drawn it assuming the riders start at the bottom and the wheel has just begun turning. You have figures for r and d which, by the way, you should check. So express y in terms of r, d, and θ. Then you can express θ in terms of time t and you will have the height of the riders, y, in terms of t, which you can graph.