Transformer.docx

TRANSFORMER/ELECTRICAL CIRCUIT PRACTICE 1. The colour code used for the transmission lines of Nigerian power system are ……….. A.Red,Yellow,Green B. Red,Green,Blue C. Red, Yellow,Blue 2. The frequency of transmission and distribution that is adopted in the design of transformers used in Nigeria is ....... A. 50kHz B. 50Hz 3.

C.30kHz

D.30Hz

The primary and secondary sides of the transformer are linked by……….. A.Electrical Conductors B.Magnetuc Circuit C. Electrical Circuit

4.

The details of a typical power distribution transformer is contained in the …………. A.Detail plate B.Data plate C.Name plate D. Description plate.

5.

Fig 1. The figure above represents --------------------------------- type of ac circuit rectification A.Full wave rectification B.Full wave Bridge rectification

C.Half wave rectification

D.None 6. The arrow in Fig 2 shows the flow of current during a rectification process. What cycle is represented by the direction of flow of current.

Fig 2. A.Negative Half- Cycle B.Positive Half-Cycle C.Negative Full wave Cycle D.Positive Full-Wave Cycle. 7. The following are important parameters to consider when choosing a smoothening capacitor for a rectified ac circuit. A.Its Working voltage and circuit resistance

B.Its Capacitance Value and Circuit

Resistance C.Circuit Resistance and Circuit Reactance.

D.Working Voltage and its

Capacitance Answer True or False for the statements in question 8-10 8. The transformer oil performs the function of cooling and voltage regulation in the transformer………………….. 9. The current transformer is not suitable for metering in the electrical power industry……….. 10. A half wave rectifier is highly recommended in the design of power supply required for audio circuit…………………….