Q.1/ Choos a, b, c, or d: 1- Which of the following factors would decrease the resistance of the electrical wire? a. Increasing the resistivity b. Increasing the cross-sectional area of wire. c. Decreasing the cross-sectional area of wire. d. Increasing the length of wire. 2- What will be the resistivity of a metal wire of 2 m length and 0.6 mm in diameter, if the resistance of the wire is 50 2. a. 70.65 x 107 Qm b.75.65x107 2m c. 55.65x107 2m d. 80.65x107 Qm 3- A cable has a resistance of 27 2 at a temperature 35 °C and the temperature coefficient of resistance at 0 °C is 0.0038. The resistance of cable at 0°C is: a. 23.83 2 b. 20.83 2 c. 28. 23 N d. 13.24 2 4- Consider a circuit with two unequal resistances connected in parallel, then:

Q.1/ Choos a, b, c, or d: 1- Which of the following factors would decrease the resistance of the electrical wire? a. Increasing the resistivity b. Increasing the cross-sectional area of wire. c. Decreasing the cross-sectional area of wire. d. Increasing the length of wire. 2- What will be the resistivity of a metal wire of 2 m length and 0.6 mm in diameter, if the resistance of the wire is 50 2. a. 70.65 x 107 Qm b.75.65x107 2m c. 55.65x107 2m d. 80.65x107 Qm 3- A cable has a resistance of 27 2 at a temperature 35 °C and the temperature coefficient of resistance at 0 °C is 0.0038. The resistance of cable at 0°C is: a. 23.83 2 b. 20.83 2 c. 28. 23 N d. 13.24 2 4- Consider a circuit with two unequal resistances connected in parallel, then:

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter12: Electronic Control Devices

Section: Chapter Questions

Problem 14RQ

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