CONNECTING ELECTRICAL CIRCUITS

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CONNECTING ELECTRICAL CIRCUITS

When electrical components are connected, they may be placed either end on end (called series circuit) or side by side (called parallel circuit).

SERIES CIRCUITS :

When circuit components are connected with only one conducting path they are said to be connected in series. The same current is in all components. When batteries are connected in series, (the voltage obtained in the circuit will be a total of the voltage in the batteries. This principle is used in car batteries and many radio batteries, where voltages larger than 1.5 or 2 volts are required. In these cases the cells are joined together in series. If resistors are connected in series the resistance in the circuit will be equal to the sum of all resistors.

i.e.
 R = R1 + R2 + R3 + R4

PARALLEL CIRCUITS :

When circuit components are connected with several conducting paths between the sources of e.m.f. they are said to be connected in parallel. When batteries are connected in parallel the voltage remains the same as each cell. Parallel circuits are used in home wiring. There are as many circuits as there are appliances to be run. Each appliance receives the same voltage.
If resistors are connected in parallel then each resistor uses only the power required for its own purpose. This means a higher amperage in the circuit. This multiplies the amperage available and lengthens the time for a given amperage.


SERIES-PARALLEL COMBINATION OF RESISTANCES
 Figure shows the arrangement of series-parallel combinations of resistances. In this circuit the current divides itself into two branches as shown in Figure.

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