Using a Voltage tester pen to measure the light of a circuit, will the circuit have electricity? What can go wrong?
What is "electricity"
First of all, we have to figure out what is "electricity". Under normal circumstances, what we call "electricity" means that a continuous and stable current can be generated in the circuit, and the current must be large enough - at least as large as Just to make the appliance work.
In order to meet these requirements, the following three requirements must be met:
1. There must be a stable voltage in the line;
2. The voltage value cannot be too low;
3. The line must be a complete closed loop.
So, can these three results be measured with just one electroscope? The answer is no!
