- #1

princejan7

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**Need help on some questions -- Moments, Bearings & Trusses**

Hi guys, just have some general queries on a couple of problems :

1) http://i1097.photobucket.com/albums/g357/princejan7/reactiondirection_zps85d28093.png

They got the moment of the force BC about A by splitting into components at B and then summing up the individual moments.

Would you get the samet magnitude for the moment if you split the force at some other point on BC's line of action, eg. at C?

2) http://s1097.photobucket.com/user/princejan7/media/bearings_zps342d5a2a.png.html

Don't the thrust and journal bearings prevent rotation about the x and z axis?

The solution doesn't seem to have included these reaction moments. Why is this?

3) http://i1097.photobucket.com/albums/g357/princejan7/truss_zps5c6d8f88.png

In general, when considering the forces on the joints of a truss, how should I know which direction the forces act in?

At the point C, why do BC and CG act in opposite directions?

thanks for any help!