What is the torque exerted by T about point O?

[Auburn2017]

Homework Statement

The problem is shown in the image attached.

Homework Equations

∑F = -235i -Fi +Tcos25i + Tsin25j +210cos25i +210sin25j
Moment = r x F[/B]

The Attempt at a Solution

I have tried various things. I tried summing all the moments and then setting that equal to zero to find T. I have tried just adding the forces and setting equal to zero to find T. None of these approaches have helped so far. Right now I am just interested at find T. Could someone just point me in the right direction to start. Thanks much.

 

[billy_joule]

I have tried various things. I tried summing all the moments and then setting that equal to zero to find T.

That approach will find T. Show your work and we'll see what went wrong.

 

[Hamal_Arietis]

Chose the positive for finding moment. You must use ΣM=0.
Note M=||rxF||=r.F.sina

 

[Auburn2017]

That approach will find T. Show your work and we'll see what went wrong.

This is what I get. I also know if the distance between the force and the point is perpendicular then the moment just equals rF. If you do this then you can get the right answer but I do not understand the sign on the four terms...

 

[haruspex]

This is what I get. I also know if the distance between the force and the point is perpendicular then the moment just equals rF. If you do this then you can get the right answer but I do not understand the sign on the four terms...

Let's just consider the moment due to T to begin with. The moment is the force times the perpendicular distance between the axis and the line of action of the force, right? What is that perpendicular distance?

 

[Auburn2017]

Let's just consider the moment due to T to begin with. The moment is the force times the perpendicular distance between the axis and the line of action of the force, right? What is that perpendicular distance?

Easy.. 0.1m

 

[haruspex]

Easy.. 0.1m

So what torque does T exert about O?