Humans were essentially hunters and gatherers. They had developed the use of fire. B â¦ ut they did not live a settled existence, instead following herds of animals on their migrations which were their primary source of food. Men were the hunters and responsible for the group's primary food source.
Emf - is the amount of energy of any form that is changed into electrical energy per coulomb of charge. pd - is the amount of electrical energy that is changed into other forms of energy per coulomb of charge. Sources of emf: Cell, battery (a combination of cells), solar cell, generator, dynamo, thermocouple.
The maximum emf of a galvanic cell is called the cell potential, Ecell. It is measured with a device that draws negligible current during the experiment. Ecell depends on the composition of the electrodes and the concentrations of the ions in each of the half-cells.n a competition for electrons, the half-reaction having the higher (more positivie) reduction potential undergoes reduction. The half-reaction with the lower reduction potential is therfore forced to undergo oxidation.