A cylinder of mass 10 kg and radius 15 cm is rolling perfectly on a plane of inclination 300. The coefficient of static friction μs = 0.25.

A. How much is the force of friction acting on the cylinder?


B. What is the work done against friction during rolling?


C. If the inclination q of the plane is increased, at what value of q does the cylinder begin to skid, and not roll perfectly?

Given,


Mass of the cylinder, m = 10 kg


Radius of the cylinder, r = 15 cm = 0.15 m


Inclination angle, θ = 300


Coefficient of static friction, μs = 0.25


The moment of inertia of the cylinder about its geometric axis is given by, I = 0.5mr2


The free diagram of the body is given by,


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We have,


A. From the newton second law of motion, force net,


Fnet = ma


Where,


m = mass of the body


a = acceleration of the body


mg sinθ – f = ma


f = ma – mg sinθ


= (10×3.27)-(10×9.81×sin30)


= 16.3 N


B. During rolling the instantaneous point of contact have zero velocity. Thus, work done against frictional force is zero.


C. For rolling without skid, we have,


3μ = tan θ


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