A technician mistakenly connects the primary coil of a 1:2 step-up transformer directly to a steady 12-volt automotive battery. After the initial connection is made and the circuit reaches a steady state, what voltage is continuously induced across the secondary coil, and what is the fundamental reason for this result?
- 0 volts, because a steady direct current creates a static magnetic field that cannot induce a continuous voltage.Answer
- B24 volts, because the transformer winding ratio doubles the input voltage regardless of the current type.
- C12 volts, because the direct current passes completely through the magnetic core without being stepped up by frequency alternation.
- D24 volts, because the continuous electron flow from the battery maintains a constantly expanding magnetic field.
Answer
0 volts, because a steady direct current creates a static magnetic field that cannot induce a continuous voltage.
The correct answer identifies that a 12-volt battery provides steady Direct Current (DC). While DC will create a magnetic field in the transformer's primary coil, that field will quickly become static. Electromagnetic induction requires a continuously moving or fluctuating magnetic field—which is why transformers run on Alternating Current (AC). Without a changing magnetic field, no continuous voltage is induced in the secondary coil, resulting in 0 volts.
Step-by-Step Solution
Key Concept
Direct Current (DC) characteristics vs. Alternating Current (AC) in Electromagnetic Induction