NTPC Technical Question Paper
Part 2
1. expression for ?(n): u(n)-u(n-1)/ u(n-1)-u(n+1)/ u(n)+u(n+1)/...
2. numerical on a photodiode: to calculate the responsivity/sensitivity when a specified no of incident photons cause a specified no of electron generation.
3. for a radioactive sample which decays to 12.5% of its initial value in x days, the half life is given by..
4. connect two 1? resistors in series, then connect two 1H inductors across one of the resistors such that the ckt looks like a 1? resistor in series with a ?-section of a resistor and two inductors. With the series resistance on the i/p side, calc the transfer function of this ckt
5. AC signal conditioning is used for inductive and capacitive/resistive/piezoelectric transducers/all of the above.
6. lower useful input limit of a transducer is determined by
7. air-cored inductors are used for low frequency/high frequency/equal frequency operations.
8. given 4 pole-zero plots identify which one corresponds to the driving point impedance of a series resonant ckt.
9. given four unit-circle plots identify the one corresponding to a bandpass filter.
10. the sequence (2,3,4,3) is circularly even/circularly odd/circularly zero/both circularly even and odd.
11. z-transform of 3n u(n).
12. match the following with their characteristics: LED/LCD/nixie tube/optical fibre.
13. a 4 kHz signal is sampled at thrice the Nyquist rate and sent through a channel with error ?1%. Calc the bandwidth of the channel.
14. given an op-amp ckt obtain an expression for o/p voltage.
15. no. of encirclements made about the origin of the nyquist plot of the open loop TF:1/[(s-1)(s+2)(s+3)].
16. given a two port network in the form of a T find o/p admittance in terms of y-parameters.
17. for a repeater in a PCM cable identify the correct sequence of actions amongst threshold/equalization/etc.
18. o/p of a delta modulator when a ramp input is fed to it.
19. steady state error with ramp i/p for a type-0 system.
20. creeping occurs in energy meters bcoz.
21. ultrasonic method of flow measurement cannot be used in liquids with air bubbles/has less attenuation in air compared to liquid-identify the false statement (if any) among these.
22. major cause of losses in a fibre optic cable: dispersion/total internal refraction/presence of core and cladding/
23. which layer in the OSI model is concerned with printer buffering,etc: network/session/transport/
24. given some function F(j?) calc its inverse CTFT.
25. relation between laplace and z-transform: s=z/ s=ln z/ s=( ln z/T) /
26. maxm and minm probability error among ASK,PSK,FSK,DPSK etc
27. which of the following is a non linear modulation scheme: PAM/QAM/PCM/
28. match the following functions: e-t , e-t + et, sin(?t) with causal and stable system, causal and unstable system, etc.
29. given a ckt with a 50 ? resistor in series between two voltage sources of 10 V and 5 V magnitude calc power delivered by 5 V source.
30. laplace transform of e-3tu(t)+e2tu(-t).
31. which photodetector has output affected by own intrinsic noise: PN/APD/PIN/all.
32. inverse laplace transform of 1/s2[d/ds(e-3s/s)]
33. when I mode is added to proportional control system stability increases/ decreases/ steady state performance deteriorates/damping increases.
34. reset control is another name for integral/derivative/proportional/. Control.
35. time response of system having transfer function 625/(s2+25) will be of the form
36. given some transfer function calc the peak response time.
37. the nyquist sampling rate of the function [sin(at)/t]2 will be
38. the feedback topology that results in increased i/p and o/p impedance is current series/voltage series/current shunt voltage shunt.
39. numerical on cardiac output calculation given heart rate and volume per beat.
40. in an ECG instrumentation amplifier the differential gain is provided by 1st stage/2nd stage/mismatched resistors/output stage.
41. repeat ques 40 above for the classic 3-op amp instrum amplifier.
42. EMG signals are of the order of mV/V/?V/
43. computer assisted tomography is used for
44. numerical on electrostatic instrument, to calculate deflection given spring constant, torque etc.
45. to prevent loading of a ckt i/p impedance of a CRO should bee high/low/inductive/capacitive.
No comments:
Post a Comment