Journeyman Electrical Exam with correct detailed solutions ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
What are the components of a transformer? - correct answer✔✔1. The CORE, which
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
provides a path for the magnetic lines of flux. ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
2. The PRIMARY WINDING, which receives energy from the AC source.
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
3. The SECONDARY WINDING, which receives energy from the primary winding and
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
delivers it to the load. ||\\//|| ||\\//|| ||\\//|| ||\\//||
4. The ENCLOSURE, which protects the other components from dirt, moisture, and
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
mechanical damage. ||\\//||
What are the commonly used core materials for transformers? - correct answer✔✔1. Air
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
2. Soft Iron
||\\//|| ||\\//||
3. Steel
||\\//||
When are air-core transformers used? - correct answer✔✔When the voltage source has a
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
high frequency (above 20kHz).
||\\//|| ||\\//|| ||\\//||
When are iron-core transformers used? - correct answer✔✔When the source frequency is
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
low (below 20kHz).
||\\//|| ||\\//||
When are soft-iron-core transformers used? - correct answer✔✔Where the transformer
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
must be physically small, yet efficient. Iron-core transformers provide better power transfer
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
than the air-core transformers.
||\\//|| ||\\//|| ||\\//||
What part of a transformer provides a path for the magnetic lines of flux? - correct
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
answer✔✔The core. ||\\//||
What are the components of a transformer? - correct answer✔✔1. The CORE, which
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
provides a path for the magnetic lines of flux. ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
2. The PRIMARY WINDING, which receives energy from the AC source.
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
3. The SECONDARY WINDING, which receives energy from the primary winding and
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
delivers it to the load. ||\\//|| ||\\//|| ||\\//|| ||\\//||
4. The ENCLOSURE, which protects the other components from dirt, moisture, and
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
mechanical damage. ||\\//||
What are the commonly used core materials for transformers? - correct answer✔✔1. Air
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
2. Soft Iron
||\\//|| ||\\//||
3. Steel
||\\//||
When are air-core transformers used? - correct answer✔✔When the voltage source has a
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
high frequency (above 20kHz).
||\\//|| ||\\//|| ||\\//||
When are iron-core transformers used? - correct answer✔✔When the source frequency is
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
low (below 20kHz).
||\\//|| ||\\//||
When are soft-iron-core transformers used? - correct answer✔✔Where the transformer
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
must be physically small, yet efficient. Iron-core transformers provide better power transfer
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
than the air-core transformers.
||\\//|| ||\\//|| ||\\//||
What part of a transformer provides a path for the magnetic lines of flux? - correct
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
answer✔✔The core. ||\\//||
