In an amusement-park ride, riders stand with their backs against the wall of a spinning vertical cylinder. The ﬂoor falls away and the riders are held up by friction. The acceleration of gravity is 9.81 m/s².

If the radius of the cylinder is 10 m, ﬁnd the minimum number of revolutions per minute necessary when the coeﬃcient of static friction between a rider and the wall is 0.5.

Answer in units of rev/min.

Question

In an amusement-park ride, riders stand with their backs against the wall of a spinning vertical cylinder. The ﬂoor falls away and the riders are held up by friction. The acceleration of gravity is 9.81 m/s².

If the radius of the cylinder is 10 m, ﬁnd the minimum number of revolutions per minute necessary when the coeﬃcient of static friction between a rider and the wall is 0.5.

Answer in units of rev/min.

geerky42 · Answer

@lachlanrob 
@Algebraic! 
@NoelGreco

anonymous · Answer

I think the question is asking you to calculate the minimum number of rpm to keep the riders from falling. I don't know the equation for this though sorry.

anonymous · Answer

the normal force between the wall and the rider provides the centripetal force.
u*N must be => mg
N=mg/u
mg/u =mV^2/r
sqrt(rg/u) = V
you can find RPMs easily now?

geerky42 · Answer

could you clarify the question by draw it out? i know what question is asking for but i couldn't understand exactly what is going on... i have bad reading comprehension...

anonymous · Answer

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