Balance Experiment: Does a Hung Weight Act as if Fixed at n?
A planned test and the rule that a weight hangs perpendicular to its arm
Marked 'Experiment for tomorrow,' this page sets up a balance (staff 2 f, pivot h, arm-midpoints n and 1) carrying a spherical weight 3 at point 1 and a second weight (3 and d) hung by cords below points 2 and 1, with a dotted vertical marking the perpendicular from n to d. Leonardo plans to test whether the free weight d behaves as though attached at n, setting aside the pull it exerts on its cord. He then states the general rule that a weight always hangs perpendicularly beneath the portion of the balance-arm above it, however many cords and attachment points support it.
On this page
The planned balance test with weight d
Using balance 2 f (pivot h, midpoints n and 1), Leonardo means to carry out the experiment and derive a general rule for the simple weight d, deciding whether it functions as though it were attached at n. He deliberately leaves aside the question of the force that weight d exerts on its cord.
Rule: a weight hangs perpendicular beneath its arm
He states that the weight is always perpendicularly beneath the part of the balance-arm that stands above it. This holds even though the weight may be sustained by many cords originating from various locations on the two arms of the balance.