Static Equilibrium don't understand something

[Femme_physics]

Static Equilibrium...don't understand something

http://img135.imageshack.us/img135/4664/helpo.jpg


Look at the equation at "sum of all forces on y axis" and please tell me: How the heck did 0.4Na -mg = 0 turn into Na = 2.5m g?

 

[RonL]

http://img135.imageshack.us/img135/4664/helpo.jpg


Look at the equation at "sum of all forces on y axis" and please tell me: How the heck did 0.4Na -mg = 0 turn into Na = 2.5m g?

Sorry I can't do math, but I think you will find the answer if you look at the pipe thickness (100mm) and the vertical distance between A and B (200mm).

 

[Femme_physics]

What do these distances have to do though with the sum of all forces on the y axis? Distances are only used in moments equations.

 

[Doc Al]

Look at the equation at "sum of all forces on y axis" and please tell me: How the heck did 0.4Na -mg = 0 turn into Na = 2.5m g?

Hint: 1/0.4 = ?
Or: 2.5 X 0.4 = ?

 

[Femme_physics]

Oh, that's right, how could I forget that always in life we're followed by an invisible multiple of one...heh, thanks, I'll see how solvable it gets now :)