|
|
|
Home » Placement papers » BEL Paper Technical Electronics-Experience- 9 June 2011 at Delhi
Number of Views: 400
Date Of Addition: Wednesday, November 09, 2011
1. Simplified unit of a subtractor 2. Cascaded group of the flip-flop 3. Binary ripple counter 4. Data selector 2. The energy of the photo electron depends upon the following factor 1. Intensity of incident radiation 2. Quality of the photocathode 3. Frequency of incident radiation 4. Type of the incident light source 3. Hall effect is used to determine 1. Magnetic flux 2. Current density 3. Type of semiconductor material 4. All of the above 4. Which one of the following is the thermistor 1. Semiconductor device 2. Microwave device 3. Platinum resistance thermometer 4. Thermo-couple device 5. Silicon is having direct band gap 1. True 2. False 3. No gap 4. None of these 6. Boron is doped in silicon to form 1. P-type 2. N-type 3. Intrinsic 4. None of these 7. The concentration of impurity in doped silicon semiconductor per atom is 1. 1018 b. 1022 c.108 d.10-22 8. Conduction in P-type semiconductor is due to 1. Movement of hole 2. Movement of electron 3. Movement of atoms 4. Movement of electron-hole pair 9. Slope of electrical conductivity Vs temperature in semiconductor is 1. Positive 2. Negative 3. Linear 4. No effect 10. Volt equivalent of temperature of silicon at room temperature (300 deg K) is 1. 0.7V b. 1.1V c. 0.026V d. 16V 11. Carbon is not used as semiconductor because 1. It does not belong to silicon group 2. It is a good conductor 3. It is not a conductor 4. Band gap is very high 12. In forward bias of P-N junction depletion region 1. Increases 2. Decreases 3. Remains the same 4. Breaks down 13. Knee voltage in diode stands for 1. Reverse break down voltage 2. Saturation voltage 3. Threshold of current conduction 4. Peak inverse voltage 14. An ideal semiconductor diode for an AC input acts like 1. Unidirectional switch 2. Bidirectional switch 3. Cuts off AC part 4. Power booster 15. Reverse saturation current in P-N junction diode is due to 1. Hole conduction 2. Electron conduction 3. Minority carrier conduction 4. Majority carrier conduction 16. In the zener diode the break down in the reverse characteristic current is due to 1. Electrons 2. Hole 3. Electron hole pair 4. Crystal ions 17. The percentage of voltage regulation is defined as 1. V no load – V load r100 / V load 2. V load – V no load r100 / V load 3. V load – V no load r100 / V no load 4. V no load r100 / V load 18. Filtering is effected by shunting the load with a 1. Capacitor 2. Resistor 3. Inductor 4. None of these 19. Without applying the biasing voltage the transistor current would be 1. Maximum 2. Minimum 3. No change 4. Zero 20. In the transistor the doping at the emitter is much larger than the base results in 1. Emitter current entirely of holes 2. Emitter current entirely of electrons 3. Base current is due to electron-hole pair 4. Emitter does contribute carrier which can reach collector Answers :- 1. b, 2. c, 3. d, 4. d, 5. a, 6. a, 7. a, 8. a, 9. b, 10. c, 11. b, 12. b, 13. c, 14. a, 15. c, 16. c, 17. a, 18. a, 19. b, 20. b Be the first one to comment on this Placement Paper
|
|
||||||||||||||
