Calculating Moments About a Point

[Bolter]

Homework Statement

See below

Relevant Equations

moment = force x perpendicular distance

Not sure if I answered this question right

I took my clockwise moments as +ve and counter-clockwise moments as -ve

Any help would be much appreciated! Thanks

 

[TSny]

Should $F_x$ be positive or negative?

Are you sure you took clockwise as positive for the moments? Does $F_y$ tend to rotate the object clockwise or counterclockwise?

 

[Bolter]

Should $F_x$ be positive or negative?

Are you sure you took clockwise as positive for the moments? Does $F_y$ tend to rotate the object clockwise or counterclockwise?

Oh it looks like Fy is trying to rotate the bar counter-clockwise
whereas Fx is also rotating it counter-clockwise?

so let's say I took counter-clockwise to be a positive moment, then the moment about O is (Fx * 0.15) + (Fy * 1.5) = 3.74 kN?

 

[Lnewqban]

It looks OK to me.

 

[TSny]

Oh it looks like Fy is trying to rotate the bar counter-clockwise
whereas Fx is also rotating it counter-clockwise?

Yes

so let's say I took counter-clockwise to be a positive moment, then the moment about O is (Fx * 0.15) + (Fy * 1.5) = 3.74 kN?

Looks good except for the units of the answer.