# Electronics and Communication Engineering - Automatic Control Systems

### Exercise :: Automatic Control Systems - Section 1

31.

If error voltage is e(t), integral square error =

 A. e2(t) dt B. C. D. none of the above

Explanation:

Error is squared and integrated.

32.

A lag compensator is essentially a

 A. low pass filter B. high pass filter C. band pass filter D. either (a) or (b)

Explanation:

See transfer function in the equation , β > 1

where t1 = R1C1, t2 = R2C2 and t > 1.

33.

Stepper motors find applications in

 A. X-Y plotters B. numerically controlled machining equipment C. printers D. all of the above

Explanation:

Stepper motors are used in all these applications.

34.

For type 2 system, the magnitude and phase angle of the term (jω)2 in the denominator, at ω = 0, are respectively

 A. 0 and - 90° B. 0 and + 90° C. infinity and - 180° D. infinity and + 180°

Explanation:

If ω = 0, has a magnitude of infinity and phase angle -180°.

35.

In an integral controller

 A. the output is proportional to input B. the rate of change of output is proportional to input C. the output is proportional to rate of change of input D. none of the above