Question

A person stands in contact against the inner wall of
a rotor of radius r. The coefficient of friction between
the wall and the clothing is p and the rotor is rotating
about vertical axis. The minimum angular speed of
the rotor so that the person does not slip downward is​

Answer 1

Hence the angular speed ω = g μ r and  linear speed V=  g  r μ

Explanation:

As we know that:

Normal force =  Centripetal force acting on the person

N = mω^2 r

Frictional force "f" = μ N = μ m ω^2  r

Weight of the person "w" = m g f

f = W μ m ω^2

r = m g

Or we can say that:

W = g μ r

Required linear speed, V = r w = r g μ r  = g r μ

Hence the angular speed ω = g μ r and  linear speed V=  g  r μ

Answer 2

Answer:

here

Explanation:

refer to attachment.......