Consider the \$AC\$ circuit:
For various \$U\$ values set by the potentiometer, we have measured the current \$I\$ flowing through the circuit with and without core put inside the inductor \$L\$.
As a result we concluded that, without the core, the current was always bigger than with the core.
E.g.: for set \$U = 4V\$ the current with the core: \$I = 4.33 \; mA\$ and without the core \$ I = 26.9 \; mA\$.
The cylindrical-shaped core was made out of metal-alike material.
- Given the fact that with the core the current was lower, what material could the core be made of? Ferromagnetic cores increase the current, right?
- What exactly does the
Atrin the schematic stands for?