Rotational Inertia: Solve for Acceleration of Suspended Masses

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SUMMARY

The discussion focuses on calculating the acceleration of two suspended masses in a pulley system, where the pulley has a mass of 0.2 kg and a radius of 0.015 m, experiencing a torque of 0.35 Nm due to friction. The relevant equations include torque (T = I * α) and the moment of inertia (I = 1/2 * m * r²). The initial calculations yield an angular acceleration of 233.333 rad/s², which translates to a linear acceleration of 3.5 m/s². Further clarification is needed on incorporating the masses and tensions in the strings to find the net acceleration using Newton's laws.

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  • Understanding of Newton's laws of motion
  • Familiarity with rotational dynamics concepts
  • Knowledge of torque and angular acceleration
  • Basic proficiency in algebra for solving equations
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  • Study the application of Newton's second law in rotational systems
  • Learn about the relationship between linear and angular acceleration
  • Explore tension in strings and its effect on pulley systems
  • Investigate the concept of net force in multi-mass systems
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Students studying physics, particularly those focused on mechanics and rotational dynamics, as well as educators looking for practical examples of pulley systems and torque calculations.

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Homework Statement


Two masses are suspended from a pulley system. The pulley itself has a mass of .2kg, a radius of .015m, and a constant torque of .35Nm due to friction between the rotating pulley and its axle. What is the magnitude of acceleration of the suspended masses if m1=.4kg and m2 = .8kg?


Homework Equations



Torque=I(rotational inertia) * angular acceleration
I= 1/2* m * r2


The Attempt at a Solution


T=I*a
.35= (.5)(.2)(.0152)(a)
233.333=angular acceleration

233.333/.015=3.5
3.5=linear acceleration

What do I do with the masses?
Is all that above work right?
 
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T = Ia is for T(total) you have just taken T due to friction
also use the T due to tension in strings ...

and for masses find net acceleration using newon's laws and find tension in 2 strings ... then apply T=Ia
 
could you maybe explain that with a bit more detail, I am still not sure of what to do
 

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