1️⃣ Rotor speed
2️⃣ Synchronous speed
3️⃣ Shaft torque
4️⃣ Core-loss component
✅ Answer (Detailed Solution Below)
✔️ Option 4: Core-loss component
📖 Detailed Solution
🔷 Definition of Slip
Slip of an induction motor is defined as:
Where:
➤ Ns = Synchronous speed
➤ Nr = Rotor speed
Slip is usually expressed as percentage:
🔍 Dependence of Slip
✔️ 1️⃣ Rotor Speed
From the slip formula:
If rotor speed changes → slip immediately changes.
➡ Therefore, slip directly depends on rotor speed.
✔️ 2️⃣ Synchronous Speed
Synchronous speed:
Since Ns appears in the slip equation, slip depends on synchronous speed.
✔️ 3️⃣ Shaft Torque
In the normal operating region:
When shaft load increases:
➤ Rotor slows down
➤ Slip increases
➤ Rotor current increases
➤ Torque increases
Thus, slip is indirectly dependent on shaft torque.
❌ 4️⃣ Core-Loss Component
Core losses consist of:
➤ Hysteresis loss
➤ Eddy current loss
These losses:
✔ Affect efficiency
✔ Affect power factor
✔ Increase heating
❌ Do NOT appear in slip equation
❌ Do NOT control rotor speed directly
Therefore, slip is independent of core-loss component.
📊 Summary Table
| Parameter | Does Slip Depend On It? |
|---|---|
| Rotor speed | ✅ Yes |
| Synchronous speed | ✅ Yes |
| Shaft torque | ✅ Yes (indirectly) |
| Core-loss component | ❌ No |
⭐ Important Exam Concept
✔ Slip depends on relative speed between rotor and stator field
✔ Slip increases with load
✔ Slip is independent of core losses
📌 One-Line Exam Statement ⭐
Slip of an induction motor depends on rotor speed, synchronous speed, and load torque — but not on the core-loss component.
📝 Final Conclusion
👉 Correct Answer: Option 4