Two equivalent beams sharing a load with the pivot
A small weight lifts 4 of 14 pounds, leaving 10, while the pole gains 8 — the same in both figures
Two beam diagrams are declared to be of one and the same nature. In each, applying 4 pounds — at n in the upper figure, at m in the lower — lifts 4 pounds from a 14-pound load, leaving 10, while the supporting pole gains 8 pounds. Leonardo uses the paired figures to show that the same distribution of force arises whether the small weight acts through a raised support or through a suspended arm.
On this page
Same force distribution in two beam arrangements
The two figures are said to be of the same nature. Placing 4 pounds at n lifts an equal 4 pounds from the 14 tied to the beam, leaving 10, so the pole gains 8 pounds. The lower figure behaves identically: m's 4 pounds raise 4 of the 14 pounds at b, leaving 10, while the pole bears 8, just as above.