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A ring and a disc, both with radius r and mass M, roll down an incline. Find their angular and linear accelerations.

User Pkout
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1 Answer

1 vote

Answer:

Step-by-step explanation:

Given

both ring and disc have mass m and radius r

Let
\thetabe the inclination of plane with horizontal


f_r be the friction force which provides torque to object


mgsin\theta -f_r=ma

and
I\alpha =f_r* r ---1

where I=moment of inertia


mgsin\theta -(I\aplha )/(r)=ma

and we know for pure rolling a=\alpha \times r[/tex]

thus


a=(gsin\theta )/(1+(I)/(mr^2))

Thus Linear acceleration of ring with
I=mr^2


a=(gsin\theta )/(2)

For disc
I=(mr^2)/(2)


a=(2gsin\theta )/(3)

Angular acceleration for ring


\alpha =(gsin\theta )/(2r)

For disc


\alpha =(2gsin\theta )/(3r)

User Amaresh Narayanan
by
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