| 15th May 2015 09:57 AM | |
| Quick Sam | Re: Hindustan Petroleum Corporation Limited placement sample papers As you should get sample placement papers of Hindustan Petroleum Corporation Limited, so here I am giving following sample placement papers: Hindustan Petroleum Corporation Limited Sample Placement Paper (Control Systems) 1. An open loop control system has its (a) control action independent of the output or desired quantity (b) controlling action, depending upon human judgment (c) internal system changes automatically taken care of (d) both (a) and (b) (e) all (a),(b) and (c) 2. A servo system must have (a) feedback system (b) power amplifier to amplify error (c) capacity to control position or its derivative (d) all of these (e) none of these 3. The major disadvantage of a feedback system may be (a) Inaccuracy (b) inefficiency (c) Unreliability (d) instability (e) Insensitivity 4. Properties of a transfer function (a) It is ratio of two polynomials is S and assumes zero initial conditions (b) It depends on system elements and not input and output of the system (c) Coefficients of the powers of S in denominator and numerator are all real constant. The order of denominator is usually greater than or equal to the order of numerator (d) All of these (e) It is a function which transfer one physical system into another physical system. 5. The classical analogous of a simple lever is (a) Capacitor bridge (b) transformer (c) mutual inductor (d) either of these 6. Two blocks G1(s) and G2(s) can be cascaded to get resultant transfer function as (a) G1(s) + G2(s) (b) G1(s) / G2(s) (c) G1(s) G2(s) (d) 1+G1(s) G2(s) (e) 1-G1(s)G2(s) (f) two blocks cannot be cascaded 7. The principles of homogeneity and super position can be applied to (a) linear time invariant system (b) non-linear time invariant system (c) digital control system (d) both (a) and (b) 8. Pick up the nonlinear system (a) automatic voltage regulator (b) d.c. servomotor with high field excitation (c) temperature control of a furnaces using thermistor (d) speed control using SCR (e) all of these 9. Signal flow graph (SFG) is a (a) polar graph (b) semi log graph (c) log log graph (d) a special type of graph for analyzing modem control system (e) a topological representation of a set of differential equations 10. Disadvantages of magnetic amplifier (a) time lag, less flexible, non-sinusoidal waveform (b) low power consumption and isolation of the active circuit (c) saturation of the core (d) all of these 11. Pick up false statement regarding magnetic amplifiers (a) The gate coil of an ideal magnetic amplifier has either zero or infinite inductance (b) Resistance of control and gate winding is very small (c) Magnetic amplifier gas dropping load characteristics (d) Magnetic amplifiers are not used to control the speed of d.c. shunt motor (e) Magnetic amplifiers can be used in automatic control of electric drivers of higher rating. 12. High power amplification is achieved by using (a) push pull amplifier (b) amplidyne (c) magnetic amplifier (d) DC amplifier (e) D.C. generator 13. Pick up false statement regarding servomotors (a) The d.c. servomotors are lighter than equivalent a.c. servomotors (b) The d.c. servomotors develops higher starting and reversing torque than equivalent a.c. servomotor. (c) A drag cup a.c. servomotor has one windings on stator and other on rotor (d) Output power of servomotors varies from 1/20 W to 100 W 14. To reduce steady state error (a) decrease natural frequency (b) decrease damping (c) increase damped frequency (d) increase time constant (e) increase gain constant of the system 15. A good factor for Mp should be (a) less than 1 (b) lying between 1.1 and 1.5 (c) more than 2.2 (d) zero (e) infinity 16. Pick up false statement. Routh-Hurwitz criterion (a) is used for determining stability of a system (b) is an algebraic procedure (c) gives the exact location of roots of the characteristic equation (d) does not indicate relative degree of stability or instability 17. Which of the following is the time domain method of determining stability of a control system (a) Bode plot (b) Nyquist plot (c) Nicholos chart (d) Routh-Hurwitz array (e) Constant M and (fy) locus (f) Root locus technique 18. The technique which gives transient response quickly as well as stability information is (a) Nyquist plot (b) Routh-Hurwitz criteria (c) Bode plot (d) Root locus plot (e) Nichols plot 19. The bandwidth can be increased by use of (a) phase lag network (b) phase lead network (c) both (a) and (b) in cascade (d) both (a) and (b) in parallel (e) none of these 20. Nyquist plot is drawn on (a) semi log graph paper (b) log log graph paper (c) polar graph paper (d) centimeter graph paper 21. If the gain margin is positive and the phase margin is negative the system is (a) stable (b) unstable (c) indeterminist 22. The Bode plot is applicable to (a) all phase network (b) minimum phase network (c) maximum phase network (d) lag lead network (e) none of these 23. The valid relation between setting time ts and rise time tr is (a) tr>ts (b) ts>tr (c) ts=tr (d) none of these 24. As a root moves further away from imaginary axis the stability (a) increases (b) decreases (c) not affected (d) none of these 25. Flat frequency response means that the magnitude ratio of output to input over the bandwidth is (a) variable (b) zero (c) constant (d) none of above |
| 15th May 2015 09:57 AM | |
| Unregistered | Re: Hindustan Petroleum Corporation Limited placement sample papers Can some one provide me sample placement papers of Hindustan Petroleum Corporation Limited? |
| 12th November 2014 03:30 PM | |
| Kiran Chandar | Re: Hindustan Petroleum Corporation Limited placement sample papers The Hindustan Petroleum Corporation Limited offers the recruitments for the following branches. These are as follows: Mechanical Civil Electrical Electronics & Telecommunications Instrumentation Chemical You are asking for the HPCL Electronics and electrical Placement-Papers. Here I am providing this. This is as follows: 1. The unit of magnetic flux density is (A) gauss (B) tesla (C) bohr (D) weber/sec Ans: (B) 2. The equation of continuity defines the relation between (A) electric field and magnetic field (B) electric field and charge density (C) flux density and charge density (D) current density and charge density Ans: (D) 3. The current in a coil changes from 5A to 1A in 0.4 second. The induced voltage is 40 V. The self inductance in henry is (A) 1 (B) 2 (C) 4 (D) 10 Ans: (C) 4. The maximum power will be transferred from a voltage source to a load when (A) the source impedance is half that of the load impedance (B) the source impedance is equal to that of the load impedance (C) the source impedance is twice that of the load impedance (D) both source and load impedances must be zero Ans: (B) 5. The total number of branches in a network is equal to b. The graph of the network has n number of branches. The minimum number of line currents is (A) b+n (B) b (C) b-n (D) n Ans: (C) 6. In a travelling electromagnetic wave, E and H vector fields are (A) perpendicular in space . (B) parallel in space. (C) E is in the direction of wave travel. (D) H is in the direction of wave travel. Ans: C 7. A wave is incident normally on a good conductor. If the frequency of a plane electromagnetic wave increases four times, the skin depth, will (A) increase by a factor of 2. (B) decrease by a factor of 4. (C) remain the same. (D) decrease by a factor of 2. Ans: D 8. A hollow rectangular waveguide acts as a (A) High pass filter (B) Low pass filter (C) Band pass filter (D) Low frequency radiator Ans: A 9. Divergence theorem is applicable for (A) static field only (B) time varying fields only (C) both static and time varying fields (D) electric fields only Ans: C 10. For a rectangular wave guide, 2.5cm x 1.2cm, dominant cut off wavelength is (A) 5 cm (B) 2.5 cm (C) 2.4 cm (D) 3.7 cm Ans: A 11. When a steady current is passed through a ballistic galvanometer, then the deflection will be (A) maximum (B) zero (C) twice the normal value as it depends on Hibbert magnetic standard (D) None of the above Ans: (B) 12. The measurement of frequency can be carried out with (A) Owen’s bridge (B) Wien’s bridge (C) Maxwell’s inductance-capacitance bridge (D) Schering’s bridge Ans: (B) 13. The following material is not used for making a piezoelectric transducer (A) Rochelle salt (B) Barium titanate (C) Chlorium sulphide (D) Quartz Ans: (C) 14The velocity factor of a transmission line (A) is governed by the relative permittivity of the dielectric. (B) is governed by the skin effect. (C) is governed by the temperature. (D) All of the above. Ans: A 15. By using feedback in control systems, the sensitivity to parameter variation is improved.This is achieved at the cost of (A) stability (B) loss of system gain (C) transient response (D) reliability Ans: (B) 16. The phase-lead compensation is used to (A) increase rise time and decrease overshoot. (B) decrease both rise time and overshoot (C) increase both rise time and overshoot (D) decrease rise time and increase overshoot Ans: (B) 17. In position control systems, the device used for providing rate feedback is called (A) potentiometer (B) synchro (C) tachogenerator (D) servomotor Ans: (C) 18. Given a badly underdamped control system, the type of cascade compensator to be used to improve its damping is (A) phase-lead (B) phase-lag (C) phase-lag-lead (D) notch filter Ans: (B) 19. Analog data acquisition systems are used when (A) wide bandwidth and low accuracy are required/sufficient (B) narrow bandwidth and low accuracy are required/sufficient (C) wide bandwidth and high accuracy are required (D) narrow bandwidth and high accuracy are required Ans: (A) 20. In a transmission line terminated by characteristic impedance, Zo (A) There is no reflection of the incident wave. (B) The reflection is maximum due to termination. (C) There are a large number of maximum and minimum on the line. (D) The incident current is zero for any applied signal. Ans: A |
| 12th November 2014 12:11 PM | |
| Unregistered | Hindustan Petroleum Corporation Limited placement sample papers I am student of the Electronics and electrical? I am searching for the HPCL Electronics and electrical Placement-Papers? Please tell me from where I can download this? |
