# Help with a torque-rotational-inertia-force question please!

1. Nov 3, 2005

### Windwaker2004

A cylindrical fishing reel has a moment of inertia of I=6.22×10-4 kg·m2 and a radius of 4.44 cm. A friction clutch in the reel exerts a restraining torque of 1.34 N·m if a fish pulls on the line. The fisherman gets a bite, and the reel begins to spin with an angular acceleration of 66.5 rad/s2. What is the force of the fish on the line?

I would like to know if the proper acceleration to use here to calculate force would be the tangential acceleration. Also, when I use T = Fxr... does the value of F get subtracted from the force the fish is pulling with? I also can't figure out how to use the inertia in this because if I solve for mass using I = MR^2 .... thats the mass of the reel which makes no sense in using to calculate force. Anyway any help would be greatly appreciated! Thanks in advance!

2. Nov 4, 2005

### Fermat

You just work with angular acceleration.

The eqn to use here is T= Iα

You are given the values of I and α, so what is the torque providing this (angular) accln ?

You are given the resisting torque of the reel, so what must be the additional torque supplied by the fish ?

And finally, what must be the force giving this torque ?

3. Nov 4, 2005

### Windwaker2004

Thank you so much for your help. I made it a lot more complicated than that method. I worked it out and got the correct answer. Thanks again!