NMDC Placement Paper

                                                 NMDC Placement Paper

1. The propagation of light through an optical fiber goes by the principle
(1)Refraction
(2) Totalinternalreflection
(3) Interference
(4) Diffraction

2. A block of weight 200 N is pulled along a rough horizontal surface at a constant speed by a force of 100 N acting at an angle of 30°. The coefficient of friction between the block and the surface
(1) 0.58
(2) 0.75
(3) 0.45
(4) 0.65 

3. A boy wants to climb down a rope. The rope can withstand a maximum tension equal to two thirds the weight of the boy. Ifg is the acceleration due to gravity, the minimum acceleration with which the boy should climb down the rope is
(1) g/3
(2) 2g/3
(3) 3g/2
(4) g 

4. The standard data rate of PCM in digital speech transmission is
(1)8Kbps 
(2)16Kbps
(3)32Kbps 
(4)64Kbps

5. Two sounds of wavelengths 5 m and 6 m, travelling in a medium produce 10 beats per second.The speed of sound in the medium is 
(1)300 m/s 
(2)320 m/s 
(3)350 m/s 
(4)1200 m/s

6. Teflon is
(1)Phenol formaldehyde 
(2)An inorganic polymer
(3) Poly tetrafluoroethylene
(4)A monomer

7. The lightest particle is
(1) Positron
(2) Neutron
(3) Proton
(4) a-particle 

8. The Fastest ADC is
(I)Successive Approximation type 
(2) Counter type
(3) Flash type
(4) Dual Slope type

9. The size of internal RAM in 8051 microcontroller is
(1) I Mbytes
(2) I Kbytes
(3) 512 bytes
(4) l28 bytes 

10. The size of instruction queue in 8086 microprocessor is ------------- bytes.
(1)3 
(2)4 
(3) 5 
(4)6

11. The 80386 is a ----------- bit microprocessor.
(I)8 
(2)16 
(3)32 
(4)64

12. The combination of primary colours Blue and Red yields
(1) Yellow
(2) Cyan
(3) Magenta
(4) White

13. The domain name given for nonprofit professional organizations is
(1) .com
(2) .edu
(3) .org
(4) .gov 

14. The threshold voltage for a silicon diode is
(1)0.1 
(2)0.3 
(3)0.7 
(4)1.1

15. The diode that exhibits negative resistance characteristics is
(1)Zener diode 
(2) Tunnel diode
(3) Varactor diode 
(4) PN junction diode

16. The number of diodes in center tapped and bridge rectifiers respectively are 
(1)2,2 
(2)4,2 
(3)4,4 
(4)2,4

17. At Pinch-Off, the drain current is 
(I) Zero
(2) Maximum
(3) Constant
(4) Infinity 

18. Astable multivibrator has stable states.
(I)0 
(2) I 
(3)2 
(4)4

19. Which of the following is energy storing device?
(l)Inductor 
(2) Capacitor
(3) Both Inductor and Capacitor 
(4) Resistor

20. For a parallel resonant circuit, selectivity is defined as reciprocal of 
(1)Q- factor 
(2) Bandwidth
(3) Resonant frequency 
(4) Power

21. How the ammeter should be connected in a circuit?
(1)In series 
(2)In shunt
(3)Either in series or in shunt 
(4)None of the above

22. In a CRT, if acceleration of electron beam increases then the brightness of display
(1)Decreases 
(2) Increases
(3) Remains the same 
(4) Slightly decreases

23. A semiconductor photodiode uses ------- effect.
(1) Photoconductive
(2) Photoemissive 
(3) Photovoltaic
(4) Photoreactive 

24. Thermal runaway is not present in FET, because of
(1)Drain resistance 
(2) Voltage gain is unity
(3) Single change carvers 
(4) Current gain is unity

25. At 100% modulation, the power in each side band is ----------- of that of carrier.
(I)25% 
(2)40% 
(3)60% 
(4)50%