Cannot understand dL/dt (angular momentum changes)

[TonyEsposito]

Thanks, got it! :)

 

[Charles Link]

Thanks, got it! :)

@TonyEsposito We'd be interested in the result that you computed. Does the computed rotation that occurs in the time of $t=1.0$ seconds now agree reasonably well with the experimental observation? $\\$ With calculations by hand, without a calculator, I got an answer in the ballpark of $370^o$.

 

[TonyEsposito]

yes, everything in agreement

 

[CWatters]

Sorry guys, one last question...we are doing a very simple lab experiment, we have a disk rotating around is axis with a weight acting on it (the very basic experiment)...the disk have a mass of 0.1 Kg, the radius is 0.3 so the Inertia is 0.5*0.1*0.3^2=0.0045 the torque acting is 0.1 so the angular acceleration is:
acc=0.1/0.0045=22.22

Ok so far (you should state your units though).

so in one second the rotation done is: 0.5*0.22*1^2*(180/Pi)=636 Degrees...but this result is nosense, too large...what I'm doing wrong?

The angular displacement is indeed 0.5*α*t² = 11.11 Radians= 636 degrees.

Are you sure the torque is 0.1Nm ? Remember the weight isn't just hanging on the rope it's falling.

Edit: Sorry I seem to have missed some replies.

 

[TonyEsposito]

Sorry guysi will be honest...i have posted the question trying to extrapolate an information...al the data was made up on the spot, thanks anyway