The current that flows is AC at the mains frequency. The small current needed to light the test light passes through the capacitance between your body and the nearby ground.abdossamad2003 said:
I'm confused by your question and situation. By "test light", do you mean an isolated AC Mains Safety Detection Device? If so, the answer given by @Baluncore is correct.abdossamad2003 said:
An insulator is a material that does not allow the flow of electric current due to its high resistance to the movement of electrons. Strong insulators have very tightly bound electrons that are not easily excited to move, preventing the flow of current.
Strong insulators have a very high resistance, so they are not able to conduct any significant amount of current. However, under extreme conditions such as high voltage or temperature, a small amount of current may flow through an insulator.
Unlike conductors, strong insulators do not allow the flow of current. Conductors have low resistance and freely allow the movement of electrons, while insulators have high resistance and restrict the flow of electrons.
The current through a strong insulator is primarily determined by the resistance of the material and the applied voltage. Higher resistance and lower voltage result in minimal current flow through the insulator.
In certain conditions, such as extreme heat or high voltage, a strong insulator may experience a breakdown of its molecular structure and become a conductor. This phenomenon is known as electrical breakdown and can result in the flow of current through the insulator.