**Chemical Effect of Electric Current MCQ Questions Answers – Electrical Engineering**

1)The polar plot of a transfer function passes through the critical point (-1,0). The gain margin is

a) Zero

b) – 1 Db

c) 1 Db

d) infinity

2) The transfer function of a linear system is the

(a) ratio of the output, V_{o}(t) and input V_{i}(t).

(b) ratio of the derivatives of the output and the input.

(c) ratio of the Laplace transform of the output and that of the input with all initial conditions zeros.

(d) none of these

2) Two identical first-order system have been cascaded non-interactively. The unit step response of the systems will be

a) overdamped

b) underdamped

c) undammed

d) critically damped

3) The system with the open loop transfer function (?)(?) = 1/{?(? 2+?+1)} has a gain margin of

(a) – 6 dB

(b)0 dB

(c) 3.5 dB

(d) 6 dB

4) Which one of the following application softwares is used to obtain an accurate root locus plot ?

a) LISP

b) MATLAB

c) dBase

d) Oracle

5) A system has a single pole at origin. Its impulse response will be

a) constant

b) ramp

c) decaying exponential

d) oscillatory

6) In open loop system

(a) the control action depends on the size of the system

(b) the control action depends on system variables

(c) the control action depends on the input signal

(d) the control action is independent of the output

7) The instrument used for plotting the root locus is called

a) Slide rule

b) Spirule

c) Synchro

d) Selsyn

8) A good control system has all the following features except

(a) good stability

(b) slow response

(c) good accuracy

(d) sufficient power handling capacity

9) When the time period of observation is large, the type of the error is

a) Transient error

b) Steady state error

c) Half-power error

d) Position error constant

10) For a stable closed loop system, the gain at phase cross-over frequency should always be :

a) >20 dB

b) > 6 dB

c) < 6 dB

d) < 0 dB