| 1. | A diac is used to ? | |
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trigger a triac
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commutate a triac
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increase efficiency of a triac
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protect a triac
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Report Question| 2. | R-C triggering is preferred over resistance triggering process because it provides ? | |
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larger value of firing angle
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protects the device from getting damaged
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causes quick triggering
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provides accurate firing
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| 3. | In the reverse biased condition of an SCR ? | |
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two out of three junctions are reverse biased
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one out of three junctions is reverse biased
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all the three junctions are reverse biased
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all the three junction are forward biased
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| 4. | A light activated silicon controlled rectifier is a ? | |
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four-layer four-junction device
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four-layer three-junction device
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three-layer two-juction device
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two-layer two-junction device
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| 5. | A triac behaves like two ? | |
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inverse parallel-connected SCRs with common gate
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resistors and one diode
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four-layer diodes in parallel
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diodes in series
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| 6. | The value of peak point current of a UJT is ? | |
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very high
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very low
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high
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about 1.5 times that of valley point current
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| 7. | A triac can be fired ? | |
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only by the negative half cycle of the supply
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only by the positive half cycle of the supply
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both by the positive as well as the negative half cycles of the supply
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without any biasing
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| 8. | After firing an SCR, the gating pulse is removed. The current in the SCR will remain ? | |
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the same
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rise a little and then fall to zero
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immediately fall to zero
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rise up
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| 9. | A thyristor can be turned off by ? | |
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reducing the anode current below holding current value
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reversing the anode voltage
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both A. and B.
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none of the above.
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| 10. | An inverter, as compared to oscillators, provides output ? | |
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noiseless
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distortionless
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low voltage
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low frequency
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