I Question about the current through a strong insulator

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When a strong insulator is placed underfoot and a test light is connected to an electrical outlet, the light can still illuminate due to the small alternating current (AC) that flows through the capacitance between the body and the ground. This current, although minimal, is sufficient to activate the test light. The discussion highlights that even a thick insulator can allow current to pass through its dirty or hygroscopic surfaces, creating a path to ground. Calculations indicate that a body capacitance of 100 pF at 230 Vrms can produce an average current of approximately 6.5 µA, enough to light the test device. The inquiry about the nature of the test light suggests a need for clarification on whether it is an isolated AC Mains Safety Detection Device.
abdossamad2003
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Suppose we put a strong insulator under our feet. In this case, when we connect the test light to the electrical outlet, the light of the test light lights turn on. I wonder how the electric current can pass through the strong insulator. If we calculate, the electric current cannot be more than 10^-18 amp which cannot turn on the test light lamp in any way.
 
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abdossamad2003 said:
I wonder how the electric current can pass through the strong insulator.
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.

A thick sheet of good insulator will also conduct current across the hygroscopic dirty surface and around the edges of the sheet to ground.

Edit; Do the numbers.
Assume a minimum of 100 pF of body capacitance, 50 Hz, 230 Vrms.
Vpp = 2.8 * 230 = 650 volts slew in about 10 ms.
C = q/v = i·t/v ; i·t = c·v ; i = c·v/t
Average current; 100e-12 * 650 / 0.01 = 6.5 uA
 
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abdossamad2003 said:
Suppose we put a strong insulator under our feet. In this case, when we connect the test light to the electrical outlet, the light of the test light lights turn on.
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.

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https://www.walmart.com/ip/Fluke-FLK2AC-90-1000V-90-1000-VAC-Detector/102480670
 
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