Moment of inertia / torque question

[ptlffrty]

Deleted Deleted

 

[emptymaximum]

ummm. i think you mean to say it is attached to a solid 'brick'
$$\vec{\tau} = \vec{r} \times \vec{F}$$
where $\vec{r}$ is the position vector from the axis of rotation to where the force is acting, and $\vec{F}$ is the force.
the direction of the vector produced by the cross product is given by the right hand rule.

 

[ptlffrty]

oops. i meant disk.

 

[ptlffrty]

bump bump bump

 

[ptlffrty]

anyone? anyone?

 

[ptlffrty]

torque and moment of inertia question..

https://www.physicsforums.com/showthread.php?t=103825"

can anyone help me out?

 

[PhY_InTelLecT]

a. what is the total moment of inertia of the wheel and disk?
I1 + I2 = [ (1/2) M1 * R1^2 ] + [ M2 * R2^2 ]
= (1/2)(6)(.1^2) + (2)(.5^2) = .53

One qn.. How did u actually arrive at this?

 

[ptlffrty]

added the moment of inertia of the hoop (mr^2) witht he moment of inertia of the disk (.5mr^2).. good chance its wrong, but itdoesnt really matter at this point, i just turned the assignment in a few minutes ago

 

[PhY_InTelLecT]

Moment of inertia shld be the same as the formula for torque=F*d=mgd.
I'm not sure bout it either. But are u sure mr^2 is the right formula for moment of a force?

 

[FredGarvin]

You deleted the original question. How are we going to help if we don't know what you are asking? However, if it is a homework problem, it belongs in the homework section.