Problem 6.06 A small button placed on a horizontal rotating platform with diamet
ID: 3280291 • Letter: P
Question
Problem 6.06 A small button placed on a horizontal rotating platform with diameter 0.326 m will revolve with the platform when it is brought up to a rotational speed of 41.0 rev/min, provided the button is no more than 0.144 m from the axis. Part A What is the coefficient of static friction between the button and the platform? Express your answer to three significant figures. SubmitM My Answers Give Up Incorrect: Try Again; 2 attempts remaining Part B How far from the axis can the button be placed, without slipping, if the platform rotates at 63.0 rev/min ? Express your answer to three significant figures. Submit My Answers Give Up ContinueExplanation / Answer
a] Here the centripetal acceleration is provided by friction,
mw^2 r = u mg
w^2 r/g = u
u = (41*2pi/60)^2*0.144/9.8
= 0.271
b] w^2r = ug
r = ug/w^2
= 0.271*9.8/[63*2pi/60]^2
= 0.0610 m
= 6.10*10^-2 m