Optic fibers are mainly used for which of the following?

A. Communication
B. Weaving
C. Musical instruments
D. Food industry

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32. Who invented Bakelite?

A. Charles Goodyear
B. Leo Hendrik Baekeland
C. Roy Plunkett
D. Henry Ford

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33. Rocket engine works on the principle of

A. Newtons third law
B. Newtons first law
C. Newtons second law
D. None of these.

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34. Cryogenic engines find application in

A. Rocket technology
B. Frost free refrigerators
C. Sub-marine propulsion
D. researches in superconductivity

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35. The best and the poorest conductors of heat are respectively

A. Silver(AG) and lead(PB)
B. Copper(CU) dialuminium (AL)
C. Silver(AG)and gold(AU)
D. Copper(CU)and gold(AU)

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36. What is the main component of biogas and natural gas?

A. Ethane
B. Methane
C. Propane
D. Butane

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37. Who of the following recognized that large quantity of energy is released as a result of the fusion of hydrogen nuclei to form deuterium?

A. Enrico Fermi
B. Glenn Seaborg
C. Hans Bethe
D. Werner Heisenberg

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38. The phenomenon of total internal reflection is observed in which one of the following?

A. Glowing tube light
B. Light passing through lens
C. Sparkling diamond
D. Twinkling star.

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