Question

Given figure is the symbol for which component in the circuit?

A. Battery
B. Key
C. Resistor
D. Rheostat

Answer 1

An electric circuit is the path of flow of electrons from source of current or source of voltage. In an electric circuit, there are many components, some are active while some are passive. Some of these components are; battery, key, resistor and rheostat. We have to find which of the components is given above.

Complete answer:
In a metal, atoms are present and in the atom protons, neutrons and electrons are present. The protons and neutrons are bound to the center of the atom known as nucleus. Electrons are free to move around the atom and further valence electrons are free to move in the metals. Due to these bounded protons and neutrons, free electrons are restricted in its motion. This restriction is what leads to resistance. In electrical circuits, a resistance symbol is used but in case of a dynamic resistor which has three external waypoints, rheostat is used.
The given figure represents that rheostat.

So, the correct answer is “Option D”.

Additional Information:
Rheostat is also known as an adjustable resistor and it is used in applications that require the adjustment of current or carrying of resistance in an electric circuit. The rheostat can adjust the generator, dim lights and it can also start or control the speed of motors.

Note:
The resistor, resistance and inductance are different from each other and their symbols are also different. The resistor represents a drop in voltage while in an inductor, energy is stored but the rheostat represents dynamic resistance and the resistance of the rheostat can change by its upper external point which is shown in the main figure.