Purposes of Series resistance is added to a circuit

1.Limiting current:

Adding a series resistor to a circuit can help to limit the current flowing through the circuit. This can be useful in situations where high current could damage components or cause other problems

2.Voltage division:

Series resistors can be used to create voltage dividers, which can be used to reduce the voltage of a signal. By using resistors of different values, the voltage can be divided in a specific ratio.

3.Biasing:

In some circuits, a series resistor can be used to bias a component such as a transistor or diode. By placing a resistor in series with the component, the bias voltage can be adjusted to achieve the desired operating conditions.

4.Protection:

A series resistor can be used as a protective device to limit the current flowing through a component or circuit. For example, a series resistor can be used to limit the current flowing through an LED, which can help to prevent damage to the LED due to excessive current.

5.Filtering:

In some circuits, a series resistor can be used in conjunction with a capacitor to create a high-pass filter. The resistor helps to control the flow of current through the circuit, while the capacitor filters out low-frequency signals.

Overall, the addition of a series resistor to a circuit can provide a range of benefits and is a common technique used in many different types of electronic circuits..