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I have a couple questions, the first:

1.) An 80 kg man sits 9 m from the axis of a ferris wheel moving at .4 radians/sec and sits on a scale. What does the scale read at A.) The Top of the Ride, B.) The bottom of te ride, and C.) 32 degrees from the bottom of the ride.

Here is what I have so far; Fc = Force Centripical; r = radius, v = velocity; m = mass

A.The Top of the Ride

Fc = m(v^2) / r V= 9m(.4 rad) = 3.6 m/s

Fc = 80(3.6^2) / 9

Fc = 115.2 N

F = ma

m = F / a a = v^2 / r = 3.6^2 / 9 = 1.44 m/s/s

m = 115.2 N / 1.44m/s/s

m = 80 kg <--- Answer ( Doesnt seem Right )

B.The Bottom of the Ride

bring down Fc = 115.2 N

Fc = 115.2 N

F = ma

m = F / a a = v^2 / r = 3.6^2 / 9 = 1.44 m/s/s

m = 115.2 N / 1.44m/s/s

m = 80 kg <--- Answer ( Doesnt seem Right Either)

C. 32 degrees above the bottom; 0 = theta

Sin(0) = O/H = O/9 = Sin(30)(9) = O = 4.5 m

Dont know where to go from there.

Second Question

2.) The friction cofficient of static friction between a childs sneakers and a spinning platform that she is standing on is .42 The kinetic coefficient is .35 If the child weighs 28 kg and is standing 1.5 m from the center of the platform, A.) at what velocity will the child start to slide away from the center, B.) At what distance from the center will the child stop sliding

A.) Start Sliding

V = Ac - Ff Ac = v^2/r, Us = .42

V = V^2 /1.5 - Fn(.42)

V^3 = 1.5 - ma(.42)

V = cuberoot(1.5 - 28(9.8)(.42))

V = cuberoot(-113.7)

V = -4.8 m/s <--- Answer ( doesnt seem right )

B.) Distance before stop.

I have no clue, Please Help, All help would be appreciated..i am very very confused with this stuff, please help

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# Homework Help: Circular Motion Help

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