Versions Compared

Old Version 9

changes.mady.by.user Andrew E Pawl

Saved on

compared with

New Version 10

changes.mady.by.user Andrew E Pawl

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

The moment arm of a force about a specific axis of rotation can be found geometrically by constructing the force's line of action and then finding the shortest distance between the line of action and the axis. The procedure is shown in the figures below.

For vertical forces:

Image Modified

Image Modified

Image Modified

Given forces.

Construct line of action for each.

Find the shortest distance (shortest distance
always perpendicular to line of action, which
implies horizontal moment arm for vertical force).

For horizontal forces:

Image Modified

Image Modified

Image Modified

Given forces.

Construct line of action for each.

Find the shortest distance (shortest distance
always perpendicular to line of action, which
implies vertical moment arm for horizontal force).

General angles:

Image Modified

Image Modified

Image Modified

Given forces.

Construct line of action for each.

Find the shortest distance.

...