In one of these branches is placed a battery B and in another a galvanometer G; the four p Q other resistances are denoted by the letters P, Q, R, S.
As the lower block carrying the weight, and in the absence of friction and other resistances the mechanical advantage will be in the same ratio of the effort to the resistance.
He was also the first to demonstrate experimentally the difference of action between what he called a "quantity" magnet excited by a "quantity" battery of a single pair, and an "intensity" magnet with long fine wire coil excited by an "intensity" battery of many elements, having their resistances suitably proportioned.
Principle of the Equality of Energy and Work.FroIn the first law of motion it follows that in a machine whose pieces move with uniform velocities the efforts and resistances must balance each other.
The symbolical expression of this law is as follows: let efforts be applied to one or any number of points of a machine; let any one of these efforts be represented by P, and the distance traversed by its point of application in a given interval of time by ds; let resistances be overcome at one or any number of points of the same machine; let any one of these resistances be denoted by R, and the distance traversed by its point of application in the gi- en interval of time by ds; then ~.Pds=2~.Rds.