Low-voltage conductors. a. are not powerful enough to cause death from electrocution b. must exceed 480V to cause death C. are responsible for most electrocution deaths due to the frequency of contact d. are unlikely to cause injury if rubber-soled shoes are worn

Q1. Static electric fields never exist inside the good conductors. Why?

1. A 200 meter long two core cable with radius of 4 millimeter is used to transmit the electrical power. The declared voltage is 200V when the conductors carry 60A. The resistivity of the conductor is 2.85 uNcm. Estimate the percentage of voltage drop that occur in cable.

3. A 2-wire d.c. distributor A B 500 metres long is fed from point A and is loaded as under : Distance from feeding point A (in metres) Load (amperes) If the specific resistance of copper is 1-7x 10* 2m, what must be the cross-section of each wire in order that the voltage drop in the distributor shall not exceed 10 volts ? 100 300 400 500 20 40 40 50 [1-734 cm³]

Question 1 Select all that apply. Which of the following are considered to be "core losses"? 12R heating loss Flux lines that bulge out at core gaps Currents that circulate within the machine non-ferrous components Field Lines that circulate around conductors and coils Rapid Changes in Domain orientation

3. A 2-wire d.c. distributor AB 500 metres long is fed from point .4 and is loaded as under: Distance from feeding point.4 (in metres) Load (amperes) If the specific resistance of copper is 1-7x 10 Sm what must be the cross-section of each wire in order that the voltage drop in the dismbutor shall not exceed 10 volts ? 100 300 400 500 20 40 40 50 [1 734 cm]

5. It is found that the armature of a coil of wire increases from 50 ohms at 20°C to 60 ohms at 56°C. What is the temperature coefficient of resistance of the conductor at 0°C? a. 0.00750 c. 0.00936 b. 0.00625 d. 0.0208

1.How is a galvanometer be protected from excessive currents? Sketch the connections of two types of shunt.

4. In conceal knob and tubing wiring, the clearance to be maintain between conductors is     a. 45 mm     b. 76 mm     c. 55 mm     d. d. 50 mm

Q.3. Give two reasons for overloading and two reasons for short circuit and two precautions to prevent each.