# assigning, calculating weights to objects

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A structural engineer asked me to find the center of gravity of a steel truss. But not the center of a mass - I mean the actual center of gravty - taking into account the weight per linear foot of steel of all members involved. Is there a way to do this using Revit Structural or even regular Autocad?

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Welcome to the forum.

MASSPROP is an awesome command, it will only work on solids or regions.

I exploded the xrefed image here, then used union so that MASSPROP

would treat it as an assembly.

This was done in Autocad Vanilla, I am not sure, but would think that REVIT must

have it, or something like it.

As you see at the bottom of the window, there is an option to write

the information to a file too.

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A structural engineer asked me to find the center of gravity of a steel truss. But not the center of a mass - I mean the actual center of gravty - taking into account the weight per linear foot of steel of all members involved. Is there a way to do this using Revit Structural or even regular Autocad?

What is the difference between center of mass and center of gravity?

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What is the difference between center of mass and center of gravity?

There isn't a difference, unless he's a theoretical physicist working with non-uniform gravitational fields, in which case I don't think he'd be here asking questions. *Penny, Penny, Penny*

http://en.wikipedia.org/wiki/Center_of_mass

The term "center of mass" is often used interchangeably with the term center of gravity because any uniform gravitational field g acts on a system as if the mass M of the system were concentrated at the center of mass R. The center of gravity is defined as the average position of weight distribution, and mass and weight are technically different properties. However, because weight and mass are proportional, the center of gravity and center of mass refer to the same point of an object for almost all objects on and near Earth's surface. Generally, physicists prefer to use the term center of mass, as an object has a center of mass whether or not it is under the influence of gravity. In addition, the term "center of gravity" refers to the single point associated with an object where the force of gravity can be considered to act,

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That was my point. It was a trick question or the "engineer" needs to go back to school.

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