What is a Rheostat

What is a rheostat?

A rheostat can be defined as an electronic device that acts as an adjustable resistor. In an electric circuit, rheostat plays an important role in adjusting the varying resistance or the current. The word rheostat cab be better understood through its Greek roots – wherein the flow of current is explained through ‘rho’ means and ‘stat’ referring to an instrument regarding stationary. 

The working principle of rheostat is based on Ohm’s law. This can be depicted as –

R is equal to V/I

Where R refers to resistance, V refers to voltage and I refers to current. 

Thus, a rheostat can be understood as a variable resistor that is used for controlling current. The various uses of rheostat are discussed below: 

1. They can be used as a device for controlling power such as controlling the intensity of light. 

2. Rheostats can also be commonly used for calibration and tuning in circuits. 

3. Rheostats can be used in heaters for controlling temperature. 

These can be called the few main functions of a rheostat, earlier the use of a rheostat also included controlling the power of devices in terms of altering the intensity of light, motor’s speed, ovens and heaters. 

Apart from this, there are also various types of rheostats developed based on their purposes. For instance, one type of rheostat is the rotatory type, popularly used for controlling power. Slide rheostats can also be found used for the purpose of education and in the lab environment. Further, a potentiometer with three terminals can also be wired as a rheostat. Other types of rheostats can be linear and pre-set. 

Thus, this was the basis of a rheostat, the symbol of a rheostat is depicted below – 

Thus, through this, the concept of rheostat can be understood in a better way.