1. If the secondary of a transformer has twice as many turns as the primary, is the secondary voltage lower than the primary voltage? 2. What are the essential parts of a transformer? Give the role that each of them plays? 3. What are the essential parts of an alternator? Give the role that each of them plays? 4. Name the sources of losses in a transformer? 5. Name the sources of losses in an alternator? 6. While repairing a transformer, a few turns were removed from the secondary winding. What's going to happen ? 7. An ideal transformer is a transformer with no primary or secondary windings. True or false ? Justify your answer ? 8. We consider an ideal transformer fed at the primary by a sinusoidal alternating voltage. • Its yield is equal to 1? True or false ? Justify your answer • Its transformation ratio is equal to 1? True or false ? Justify your answer • Show, by means of a diagram, how to connect three single-phase transformers in star-delta and star-zigzag? 9. Name one processes from which an electromotive force can arise in a conductor?

1. No, the secondary voltage is not lower than the primary voltage. In fact, it's the opposite. If the secondary of a transformer has twice as many turns as the primary, the secondary voltage will be twice as high as the primary voltage. This is due to the transformer's principle of operation, which states that the ratio of the primary to secondary voltage is equal to the ratio of the number of turns in the primary to the number of turns in the secondary.

2. The essential parts of a transformer are the core, the primary winding, and the secondary winding. The core is made of a ferromagnetic material and provides a path for the magnetic flux. The primary winding is where the input voltage is applied, and the secondary winding is where the transformed voltage is taken out.

3. The essential parts of an alternator are the rotor, the stator, and the exciter. The rotor is the rotating part that produces the magnetic field. The stator is the stationary part where the electricity is generated. The exciter provides the initial magnetic field to the rotor.

4. The sources of losses in a transformer are mainly due to the resistance of the windings (copper losses), and the magnetic properties of the core (iron losses).

5. The sources of losses in an alternator are mainly due to the resistance of the windings (copper losses), mechanical losses (friction and windage), and magnetic losses in the core (iron losses).

6. If a few turns were removed from the secondary winding of a transformer, the secondary voltage will decrease. This is because the voltage ratio is directly proportional to the turns ratio.

7. False. An ideal transformer is a theoretical transformer with no losses, meaning it has perfect coupling (all the magnetic flux is confined to the core) and no resistance in its windings. It does have primary and secondary windings.

• True. An ideal transformer has a yield (efficiency) of 1, meaning there are no losses. • False. Its transformation ratio is not necessarily equal to 1. It depends on the turns ratio of the primary and secondary windings. • For the diagram, I'm sorry but as a text-based AI, I can't draw diagrams.

9. One process from which an electromotive force can arise in a conductor is through electromagnetic induction, which occurs when a conductor is moved through a magnetic field, causing a change in magnetic flux.