| 1. | In a mercury arc rectifier characteristic blue luminosity is due to ? | |
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colour of mercury
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ionization
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high temperature
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electron streams
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Report Question| 2. | The cathode voltage drop, in a mercury arc rectifier, is due to ? | |
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expenditure of energy in ionization
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surface resistance
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expenditure of energy in over-coming the electrostatic field
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expenditure of energy in liberating electrons from the mercury
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| 3. | The voltage drop at anode, in a mercury arc rectifier is due to ? | |
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self restoring property of mercury
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high ionization potential
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energy spent in overcoming the electrostatic field
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high temperature inside the rectifier
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| 4. | In a mercury arc rectifier positive ions are attracted towards ? | |
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anode
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cathode
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shell bottom
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mercury pool
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| 5. | In which of the following applications, direct current is absolutely essential ? | |
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Illumination
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Electrolysis
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Variable speed operation
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Traction
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| 6. | Which of the following metals is generally manufactured by electrolysis process ? | |
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Load
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Aluminium
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Copper
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Zinc
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| 7. | A rotary converter is a single machine with ? | |
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one armature and one field
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two armatures and one field
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one armature and two fields
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none of the above
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| 8. | Selenium rectifier can be operated at temperatures as high as ? | |
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25ºC
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40ºC
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60ºC
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75ºC
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| 9. | Which of the following rectifiers have been used extensively in supplying direct current for electroplating ? | |
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Copper oxide rectifiers
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Selenium rectifiers
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Mercury arc rectifiers
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Mechanical rectifiers
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| 10. | Which of the following is the loss within the mercury arc rectifier chamber ? | |
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Voltage drop in arc
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Voltage drop at the anode
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Voltage drop at the cathode
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All of the above
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