(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

As a result of friction, the angular speed of a

wheel changes with time according to

dθ/dt=ω0*e^-σt ,

where ω0 and σ are constants. The angular

speed changes from an initial angular speed

of 3.96 rad/s to 3.46 rad/s in 3.92 s .

Determine the magnitude of the angular

acceleration after 2.44 s.

Answer in units of rad/s2

2. Relevant equations

dω/dt = [tex]\alpha[/tex]

3. The attempt at a solution

I've tried differentiating the given expression for omega in an attempt to get the angular acceleration, but that didn't work because [tex]\sigma[/tex] is undefined in the problem. I've also tried taking the ln of both sides, but that didn't work either. I tried solving for [tex]\sigma[/tex] in terms of ω and ω0, but that didn't work. Finally, I tried just assuming that the acceleration is just constant from t0 to t, but that also wasn't the right answer. So, I have no idea what to try next......

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# Homework Help: Time-dependent angular acceleration problem

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