Mass Pulley System, Acceleration

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SUMMARY

The discussion focuses on calculating the acceleration of a mass pulley system involving a 1 kg block on a 20° incline and a 2 kg hanging block, with a friction coefficient of μk=0.45 and a frictionless pulley of mass 0.10 kg. The relevant equations include Newton's second law (ΣF=ma), rotational motion (ΣF=Iα), and the friction equation (ƒk=μN). The user initially struggled with incorporating the radius of the pulley into the tension equations but successfully resolved the issue by recognizing the need for the radius in the equation (T2-T1)=Iα. The final solution incorporates all necessary variables and calculations.

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Homework Statement


A block of 1kg is resting on an incline of 20° that has a coefficient of friction μk=0.45 with the surface. It is connected with a mass less string to a friction-less pulley of mass 0.10 kg to a hanging block of 2 kg. What is the acceleration of the system without ignoring rotational inertia. Model the pulley as a disk.

Homework Equations



First we need Newtons 2nd law, ΣF=ma
Also for rotational motion ΣF=Iα
and friction is ƒk=μN where N is the normal force.

The Attempt at a Solution


[/B]
After drawing my free body diagrams, I was left with this :

But I'm stumped there, I feel like I'm missing something obvious.

I want to plug the two equations for the tensions into the pulley equation, but then I'm still missing the radius of the pulley.

pDYs1xT.jpg

EDIT: The -m2g in the last equation on the right should be m2a

EDIT #2: I forgot the R on the (T2-T1)=IAlpha, I solved it. Thanks.
 
Last edited:
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Well done ... and good work doing all the algebra before subbing in the values.
 

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