Either because the voltage between the ends of the circuit is zero, or else
because the resistance between the ends of the circuit is enormous.
You can measure current - or the lack of current - with an ammeter.
any gadget won't work, as no current would be able to pass due to lack of electric potential difference
Yes, an electric current is the flow of charged particles.
DC current
A current.
Electric current carries electric charge. Actually to say it in the right sense, we have to say that electric current is the rate of flow of electric charges
The flow of electric charges is current.
ampere
It is called an electric current.
Voltage causes current to flow in an electric circuit.
The electric current is given by: I = V/R
A electric current produces a magnetic field