21. High resistivity materials are used in A. Precision instruments B. Heating elements C. Motor starters D. Incandescent lamps E. All of the above Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option E No explanation is given for this question Let's Discuss on Board
22. Low resistivity materials are used in A. Transformer, motor and generator windings B. Transmission and distribution lines C. House wiring D. All above applications Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
23. Most of the common metals have _________ structure. A. Linear B. Hexagonal C. Orthorhombic D. Cubic Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
24. Which of the following materials does not have covalent bonds ? A. Organic polymers B. Silicon C. Metals D. Diamond Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option C No explanation is given for this question Let's Discuss on Board
25. For germanium the forbidden energy gap is A. 0.15 eV B. 0.25 eV C. 0.5eV D. 0.7eV Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
26. Thermonic emission occurs in A. Vacuum tubes B. Copper conductors C. Ferrite cores D. Transistors Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option A No explanation is given for this question Let's Discuss on Board
27. Copper, even though costly, finds use in the windings of electrical machines because A. Copper points offer low contact resistance B. Copper can be easily soldered and welded C. Copper windings are less bulky and the machines become compact D. All of the above Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
28. _______ has zero temperature co-efficient of resistance. A. Aluminium B. Carbon C. Porcelain D. Manganin Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
29. Which of the following is a semiconductor material ? A. Phosphorous B. Rubber C. Silicon D. Aluminium Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option C No explanation is given for this question Let's Discuss on Board
30. Constantan contains A. Silver and tin B. Copper and tungsten C. Tungsten and silver D. Copper and nickel Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
