A series connection is a connection in which elements are connected at only one end. A sequence is characterized by the fact that it excludes any branching.
A serial connection from a parallel differs in that a parallel connection is made in which there must be at least two nodes.
Resistors are elements of artificial resistance. They are used in electronics as an additional load to reduce current or voltage of the circuit. How is this done?
If it is necessary to reduce the current, a series connection of the resistors is performed. In this case, the current of each resistance is the same, and the potential difference is different. It should be noted that the potential difference - this is the magnitude of the voltage drop, it directly depends on the resistance of the resistor.
For example, in a circuit with a voltage of 220 V there is a coil whose resistance is 1 Ohm. If a phase is applied to one of its ends and zero to the other, then a short circuit will occur in fact , since 1 Ohm is too small. There will be a huge current, the coil will burn, and the network will be knocked out. If two resistors of 500 kOhm are placed in series with the coil, then there will be no short circuit, and the coil will work as it should.
With a parallel connection, the currents of each branch will differ, and the voltages will be the same. Thus, the current value of each section depends on the resistance of this section. This circuit is used to increase the voltage drop. For example, the resistance of the coil is designed for 50 V. To turn it on to the 220 V network, you must put the corresponding resistance in parallel with it. A voltage drop will be created on it, and the coil will not burn.
Thus, parallel and serial connection are used in special cases and work according to Ohm's law.
If the LEDs are connected in series, then we must remember that if at least one of them fails, the entire chain goes out. As already mentioned, there is only one current, at the point of termination the charges cease to flow, and the circuit breaks. With a parallel connection, it does not matter which LED is faulty, the rest will continue to light.
If the series resistance is carried out using the same
values of resistors, then its total value will be equal to the product of one of the resistances by the total number of elements.
If the values of the resistors are different, then their total resistance will be equal to the sum of the resistances of each element.
With a parallel connection, the calculation is carried out somewhat differently. For example, there is a chain of three resistances with values of R1, R2, R3. To find out the total resistance of the circuit in parallel connection, it is necessary to calculate the sum of the reciprocal values of these values, that is, add three fractions 1 / R1 + 1 / R2 + 1 / R3. Fractions are reduced to a common denominator - and the result is calculated. The resulting fraction is flipped and the final value is considered.
In order to select the resistance for any circuit, it is necessary to correctly calculate. Some experts try to select resistors by experiment. However, even in this case, it is necessary to know at least approximately which resistor values can be optimal.