Direction of Moment: Is Book Correct?

[goldfish9776]

Homework Statement

IMO, the direction of moment of both F1 and F2 should point inside the paper , and rotate clockwise , am i right ? but the book gave different things... which is correct?

Homework Equations

The Attempt at a Solution

 

[Simon Bridge]

Please describe how you arrived at your answer.
Note, the images you provide do not appear to have F1 or F2 on them... fig 3.26a has some forces and a moment, it that what you mean?

 

[goldfish9776]

Please describe how you arrived at your answer.
Note, the images you provide do not appear to have F1 or F2 on them... fig 3.26a has some forces and a moment, it that what you mean?

there are f1 anf f2 in diagram 3.26a and 3.26b ... sinnce the moment = r X F... so, by right hand rule , the thumb( direction of moment )_ point into the paper...and the moment should be in clockwise direction... am i right ?

 

[insightful]

It's an optical illusion. You're seeing r₁ and r₂ coming out of the page. They can also be going into the page.

 

[Simon Bridge]

Make sure you have the 3d drawing convention for thr book right.