Max Speed of 0.20 kg Mass on Rotating Turntable

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The discussion centers on calculating the maximum speed (v_max) of a 0.20 kg mass on a rotating turntable without slipping, given a static friction coefficient of 0.080 and a radius of 0.15 m. The centripetal force required for circular motion is equated to the maximum static friction force to derive the formula v_max = sqrt(μ_s * r * g). Substituting the values into the equation yields a maximum speed of 0.34 m/s. The calculations confirm that the methodology used to arrive at this speed is correct. Understanding these principles is essential for analyzing motion on rotating surfaces.
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Information given:

A small metal cylinder rests on a circular turntable that is rotating at a constant speed as illustrated in the diagram View Figure .

The small metal cylinder has a mass of 0.20 \rm kg, the coefficient of static friction between the cylinder and the turntable is 0.080, and the cylinder is located 0.15 \rm m from the center of the turntable.

Take the magnitude of the acceleration due to gravity to be 9.81 \rm m/s^2


Question:

What is the maximum speed v_max that the cylinder can move along its circular path without slipping off the turntable?
Express your answer numerically in meters per second to two significant figures.
 

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https://www.physicsforums.com/showthread.php?t=94379
 
The centripetal force Fc, for a body of mass m traveling with speed v in a circle of radius r is,

Fc = (mv^2)/r....eqn 1

The object to slip off the turntable if the centripetal force overcomes the maximum force due to static friction F_max:

F_s = (u_s)N = (u_s)mg...eqn 2

u_s is the coefficient of static friction.
g = 9.8 m/s^2
m = mass

Using Eq. 1 and Eq. 2 (Fc=Fs) we solve for the maximum speed vmax.

Thus v_max = sqrt((u_s)mg)

you can do the math.
 
The above process is correct but when u solve eqn1 n 2 u get
Vmax = sqrt(μs*r*g) = =0.34 m/s
 
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