c) A trictionless electric motor with an internal resistance R is connected to a

Question

c) A trictionless electric motor with an internal resistance R is connected to a power supply with a fixed EMF. Which statement is not true? 1. When the mechanical load increases the internal resistance decreases 2. The motor draws more current at low speed than at high speed 3. The motor converts electrical power into mechanical power 4. If no load is attached the motor will draw no current d) Which of the following is not true about an magnetic dipole? 1. It experiences a torque in a steady magnetic field 2. It produces a magnetic field that, at positions far from the dipole, falls off with the 3"d power of distance 3. It consists of two separate charges of equal magnitude and opposite sign 4. It aligns with an external magnetic field A discharge between two charged conductors that are separated by an insulating material will start at a sharp point because e) 1. 2. 3. 4. The sharp point damages the insulator The charge spontaneously leaks into the insulator The conductor is an equipotential The charge density is highest at the sharp point, giving the largest electric field

Explanation / Answer

C) option (4): since the motor has an internal resistance it will draw some current if no load is attached.

d) option (3): by definition a magnetic dipole is a current loop

e) option (4): so called edge effect.

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.