- #1

srecko97

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## Homework Statement

May I ask you something about a task from the last years test at faculty of mathematics and physics, University of Ljubljana, Slovenia ...

There is a disk at the end of a pole. We cause some F dt tangentally on the disk, which causes the change of momentum. I need to calculate ω for pole and for disk too. I have given mass of a pole and mass of a disk and also length and radius.

http://Fdt causes the change of angular inertia ΔG ⋅r = J ω Is it Ok if i first calculate the ω of disk and than put into equation that Jdiskωdisk = J poleωpole or is it Jdiskωdisk+J poleωpole=ΔG ⋅r and the second equation Jdiskωdisk2 +J poleωpole2=mv2 but i do not know v ... I do not have answers so i am so sceptical about my calculation "os A" means axis in point A I would be really greatful if you answer me. If you can't, it is ok too.[/PLAIN]

## Homework Equations

ΔG ⋅r = J ω

## The Attempt at a Solution

Fdt causes the change of angular inertia

ΔG ⋅r = J ω

Is it Ok if i first calculate the ω of disk and than put into equation that Jdiskωdisk = J

_{pole}ω

_{pole}

or is it J

_{disk}ω

_{disk}+J

_{pole}ω

_{pole}=ΔG ⋅(r+L)

and the second equation J

_{disk}ω

_{disk}

^{2}+J

_{ pole}ω

_{pole}

^{2}=mv

^{2}

but i do not know v ...

I do not have answers so i am so sceptical about my calculation

"os A" means axis in point A

I would be really greatful if you answer me. If you can't, it is ok too.

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