| 1. | By which of the following methods major portion of the beat generated in a H.R.C. fuse is dissipated ? | |
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Conduction
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Radiation
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Convection
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All of the above
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Report Question| 2. | The relay operating speed depends upon ? | |
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armature core air gap
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the spring tension
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the rate of flux built up
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all of the above
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| 3. | Air blast circuit breaker is used for ? | |
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intermidant duty
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short duty
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repeated duty
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over currents
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| 4. | Ionization in circuit breaker is facilitated by ? | |
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increasing field strength
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increase of mean free path
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high temperature
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all of the above
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| 5. | An efficient and a well designed protective relaying should have ? | |
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economy and simplicity
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high speed and selectivity
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good selectivity and reliability
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all of the above
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| 6. | Relays can be designed to respond to changes in ? | |
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temperature
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voltage and current
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resistance, reactance or impedance
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all above
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| 7. | Overload relays are of ...... type ? | |
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electromagnetic
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induction
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solid state
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all above
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| 8. | SF6 gas ? | |
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is non toxic
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bas pungent small
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is lighter than air
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is yellow in colour
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| 9. | Which of the following medium is employed for extinction of arc in air circuit breaker ? | |
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SF6
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Water
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Oil
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Air
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| 10. | The inductive interference between power and communication line can be minimized by ? | |
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transposition of the communication line
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transposition of the power line
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increasing the distance between the conductors
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both(a) and (b)
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