What is necessary in order for a transformer to operate?
The primary coil must have more loops than the secondary coil.
The primary coil must have fewer loops than the secondary coil.
The primary coil must be supplied with alternating current.
The output of the secondary coil must be at least 6 volts.
The correct answer is: The primary coil must be supplied with alternating current.
Transformers work based on electromagnetic induction, where a changing magnetic field induces a current in a conductor. This is why the primary coil in a transformer needs to be supplied with an alternating current, which creates a changing magnetic field that induces a current in the secondary coil. The number of loops in each coil can affect the voltage and current levels, but it is not necessary for the basic operation of a transformer. The voltage output of the secondary coil can also vary depending on the ratio of the number of turns in the coils.