C-a). The speed of a single-phase shaded-pole motor is determined by the _________________ . a) frequency of the supply b) number of poles on the stator c) both "a" and "b" d)_ neither "a" nor "b" C-b).. The single-phase shaded-pole motor has low______ torque. a) starting b) running c) both "a" and "b" d) neither "a" nor "b" C-c). The single-phase shaded-pole motor is considered nonreversible. a) true b) false

Q4. (A)- Indicate whether the following statements are true or false and correct the false statements 1. The inter pole winding is connected in parallel to field winding. 2. The produced sparks at the brushes of a de machine is due to friction losses. 3. Series DC motors are used for low torque applications. 4. In series DC generator, Increasing the load current will decrease the magnitude of the generated voltage. 5. The compensation windings are place at the pole face and used to mitigate the effect of the armature reaction.

c) A 3 phase 6 pole star connected induction machine operates from a 120 V (phase voltage) and 50 Hz supply. Given the equivalent circuit parameters shown in Table Q4, and assuming the friction and windage loss is negligible, calculate the following parameters when operating at 1200 rpm: i. The slip (%). ii. The mechanical power (W). iii. The torque (Nm). iv. The efficiency (%). v. The no load current (A). d) Determine the following parameters for the motor in Q4c at start-up (zero speed): i. The motor phase current (A). ii. The power factor. iii. The input supply power (W). Parameter Value XM Units 85 Ω Re 250 250 R Xeg R Ω 200 Table Q4

150 hp, 1760 d/d, 2,3 kV, 60 Hz, Asynchronous motor with 3 phase winding rotor, one running the conveyor belt.The rotor windings of the machine are connected in star and The nominal open circuit voltage between collector rings is 530 V. What is requested below calculate. a) Rotor winding resistance per phase b) Assuming that the line voltage is 2.4 kV, the motor delivers 40 hp at 600 rpm. the resistance value that must be placed in series (per phase) of the rotor windings for