The core of a transformer is made of soft iron. What does this mean?
The iron loses its magnetism very quickly.
The iron retains its magnetism.
The iron core melts at a low temperature.
The iron core loses its shape easily and is easily bent.
The core of a transformer is laminated. This means:
The core is made of layers to increase eddy currents
The core is made of layers to reduce eddy currents
The core is solid to increase eddy currents
The core is solid to reduce eddy currents
Which one of these statements is treu about the primary and secondary coils in a transformer?
The primary has to be made of a special material to take a current.
The secondary has to be made of a special material in order for there to be a voltage induced.
Either coil can be connected to the voltage source and act as a primary.
The secondary is connected to the voltage source.
Which one of these is the correct transformer equation?
Nprim ÷ Nsec = Vprim ÷ Vsec
Nprim × Nsec = Vprim ÷ Vsec
Nprim × Nsec = Vprim × Vsec
Nprim ÷ Nsec = Vprim × Vsec
A transformer has a primary of 12 000 turns and a secondary of 600 turns. What is the voltage from the secondary if the primary is connected to a 240 V supply?
12 V
24 V
120 V
240 V
When the primary of 1200 turns is connected to a 12 V direct current supply, the voltage from a 4800 turn secondary is:
12 V DC
Zero
3 V DC
48 V DC
When the primary of 1200 turns is connected to a 12 V alternating current supply, the voltage from a 4800 turn secondary is:
12 V DC
Zero
3 V AC
48 V AC
Which one of these induces ZERO voltage in a wire?
Moving a magnetic field past a fixed wire
Moving a wire past a fixed magnetic field.
Moving both a wire and a magnetic field in the same direction at the same speed