# Homework Help: Nonuniform circular motion merry-go-round

1. Oct 27, 2007

### AvrGang

1. The problem statement, all variables and given/known data
A 5.0-m-diameter merry-go-round is initially turning with a 4.0 s period. It slows down and stops in 20 s.
a. Before slowing, what is the speed of a child on the rim?
b. How many revoluotions does the merry-go-round make as it stops?
( Can i know what is a merry-go-round)

2. Relevant equations

3. The attempt at a solution

I solved a) like that:

V= 2(Pi)r/T
V= 2(pi)(2.5)/4
V= 3.93 m/s

b) I think this is the correct equation:
($$\theta$$)f = $$\theta$$o + $$\omega$$o t + a/2r ( t^2)

but i can't find $$\omega$$o or a

2. Oct 27, 2007

### Microzero

http://www.worldsfinestshows.com/equipment/images/MerryGoRound_1.jpg [Broken]

Last edited by a moderator: May 3, 2017
3. Oct 27, 2007

### Microzero

initially turning with a 4.0 s period ---> T
ω=2pi/T
α = △ω/△T

θf = θo + ωo t + α/2( t^2)