Conductivity Test

In order to detect the presence of conductors,the simplest test is the Conductivity Test. Conductivity of a substance is defined as ‘the ability or power to conduct or transmit heat, electricity or sound’. Here what we use is the ability to transmit electricity. When an electrical potential difference is placed across a conductor, its movable charges flow, giving rise to electric current. We would be using this property of conductors to complete the circuit connections as shown below. The material being a conductor completes the circuit and the LED glows.If the material is an insulator, the circuit will not be completed and the LED would remain off thereby indicating presence of an insulator.