Practical work. Connecting current sources
A battery is assembled from several galvanic cells. When cells are connected in series (the “+” of one to the “–” of the next) the battery voltage equals the sum of the cell voltages. When identical cells are connected in parallel (all “+” to one point, all “–” to another), the voltage stays that of one cell, but the battery can supply current for longer. To measure the voltage, set the multimeter to direct voltage (DCV), touching the red lead to “+” and the black lead to “–”. The work is done only under the teacher’s supervision, with small 1.5 V cells. The “+” and “–” poles of a cell must never be joined directly by a wire: the cell heats quickly and is damaged. Never work with the 220 V mains or with old, leaking cells.
On paper draw series and parallel diagrams for four cells, mark “+” and “–” in each and write the expected voltage. Do the real connection with the teacher.