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1. Homework Statement
2. Homework Equations
3. The Attempt at a Solution
Since there is no net torque or net force acting on the system( which consists of the system given in the picture), I applied conservation of angular momentum and energy.
I took on the L.H.S. the angular momentum or energy of the system at time t and on the R.H.S, the corresponding quantity at time t = 0.
I took the expression for ##ω_b (t) ## from the conservation of angular momentum equation as a function of ##ω_a (t) ## and substituted in the energy eqn. to get ##ω_a (t) ## as a function of t.
But, the calculation was so much that I felt first to become sure that I am on the right path.
So, am I correct so far?
About applying conservation of energy, I have a doubt.
If the total force or torque acting the system is 0, is it compulsory that the total work done is also 0?
Total force being 0 means if there is a force ## \vec F ##, then there exists either an opposite and equal force or of sum of the rest of the forces is opposite or equal to this force. So, the work done by one force gets cancelled by the other \ sum of rest of all others. Hence, the answer to the above question is yes.A
2. Homework Equations
3. The Attempt at a Solution
Since there is no net torque or net force acting on the system( which consists of the system given in the picture), I applied conservation of angular momentum and energy.
I took on the L.H.S. the angular momentum or energy of the system at time t and on the R.H.S, the corresponding quantity at time t = 0.
I took the expression for ##ω_b (t) ## from the conservation of angular momentum equation as a function of ##ω_a (t) ## and substituted in the energy eqn. to get ##ω_a (t) ## as a function of t.
But, the calculation was so much that I felt first to become sure that I am on the right path.
So, am I correct so far?
About applying conservation of energy, I have a doubt.
If the total force or torque acting the system is 0, is it compulsory that the total work done is also 0?
Total force being 0 means if there is a force ## \vec F ##, then there exists either an opposite and equal force or of sum of the rest of the forces is opposite or equal to this force. So, the work done by one force gets cancelled by the other \ sum of rest of all others. Hence, the answer to the above question is yes.A
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