Hysteresis and Leakage Losses in AC Cables

Hysteresis Losses:
- When an AC current flows through a cable, the magnetic domains in the core material of the cable change their orientation back and forth with the changing direction of the current.
- This causes a loss of energy due to the frictional forces between the domains, which is known as hysteresis loss.
- Hysteresis loss is proportional to the frequency of the current and the magnetic properties of the core material.

Leakage Losses:
- When an AC current flows through a cable, some of the current flows through the insulation and the surrounding air instead of through the conductor.
- This results in a loss of energy due to the resistance of the insulation and the air, which is known as leakage loss.
- Leakage loss is proportional to the distance between the conductors, the insulation properties, and the frequency of the current.

Copper Losses:
- When an AC current flows through a cable, there is some resistance in the conductor which causes a loss of energy due to the heat generated by the current flowing through the conductor.
- This is known as copper loss and is proportional to the resistance of the conductor and the square of the current flowing through it.

Friction Losses:
- Friction losses occur when the cable is subjected to mechanical stress or bending, which causes the conductors to rub against each other or the insulation to rub against the conductors.
- Friction losses are proportional to the mechanical stress on the cable and the type of insulation material used.

Answer:
- The question asks which losses are present in a cable carrying alternating current.
- The correct answer is option B, which states that hysteresis and leakage losses are present but not copper or friction losses.
- This is because copper losses and friction losses are related to the resistance and mechanical stress on the conductor, respectively, and are not specific to the alternating current carrying aspect of the cable.
- Hysteresis and leakage losses are both specific to AC current, as they are related to the changing magnetic fields and the flow of current through the insulation, respectively.

C is the answer