Q: For the system of the given figure, the damping ratio of closed loop poles is

The standard form of characteristic equation is . Therefore .

Q: A system has its two poles on the negative real axis and one pair of poles lies on jω axis. The system is

Poles on j x-axis lead to oscillations.

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

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

Q: Bellows converts

To measure pressure, it is convenient to convert pressure into displacement and then use a displacement transducer.

Q: In the given figure shows pole-zero plot. If steady state gain is 2 the transfer function G(s) is

The zero at - 1 gives the term (s + 1) in the numerator. The poles at (- 2 + j1) and (- 2 - j1) give (s2 + 4s + 5) term is the denominator. Gain is 2.

Q: In the given figure the input frequency is such that R << Xc, then

Voltage across capacitor lags by 90°.

Question 1

For a first order system having transfer function , the unit impulse response is

Accepted Answer

Question 2

Assertion (A): The steady state response, of a stable, linear, time invariant system, to sinusoidal input depends on initial conditions. Reason (R): Frequency response, in steady state, is obtained by replacing s in the transfer function by jω

Accepted Answer

Steady state response does not depend on initial conditions.

Question 3

For the system in the given figure. The transfer function C(s)/R(s) is

Accepted Answer

Transfer function = (G1 + 1) G2 + 1 = G1 G2 + G2 + 1.

Question 4

A lag compensator is essentially a

Accepted Answer

See transfer function in the equation , β > 1 where t1 = R1C1, t2 = R2C2 and t > 1.

Question 5

In a two phase ac servomotor rotor resistance is R and rotor reactance is X. The speed curve will be linear if

Accepted Answer

In a two phase servomotor ∠ < 1 so that torque speed curve is almost linear.

Question 6

For the system of the given figure, the damping ratio of closed loop poles is

Accepted Answer

The standard form of characteristic equation is . Therefore .

Question 7

A system has its two poles on the negative real axis and one pair of poles lies on jω axis. The system is

Accepted Answer

Poles on j x-axis lead to oscillations.

Question 8

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

Accepted Answer

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

Question 9

Bellows converts

Accepted Answer

To measure pressure, it is convenient to convert pressure into displacement and then use a displacement transducer.

Question 10

In the given figure shows pole-zero plot. If steady state gain is 2 the transfer function G(s) is

Accepted Answer

The zero at - 1 gives the term (s + 1) in the numerator. The poles at (- 2 + j1) and (- 2 - j1) give (s2 + 4s + 5) term is the denominator. Gain is 2.

Question 11

In the given figure the input frequency is such that R << Xc, then

Accepted Answer

Voltage across capacitor lags by 90°.

Question 12

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

Accepted Answer

Error is squared and integrated.

Question 13

In Bode diagram (log magnitude plot) the factor in the transfer function gives a line having slope

Accepted Answer

For term the slope is -20 dB/decade or -6 dB/octave because - 20 log 2 = -6 dB.

Question 14

For the given figure,

Accepted Answer

For the inner loop, transfer function = Then .

Question 15

For the given figure C(s)/R(s)

Accepted Answer

.

Question 16

The given figure shows a pole zero diagram. The transfer function G(j1) is

Accepted Answer

Join j1 point with the zero and poles. Find magnitude and phase angles of all these lines.

Question 17

In the given figure, of potentiometer V0 = Vi (R0/Ri) only when

Accepted Answer

If RL is not infinite, the voltage ratio of potentiometer depends on the value of RL. This is called loading effect.

Question 18

Bode magnitude plot is drawn between

Accepted Answer

Frequency is plotted on log scale and magnitude is taken in dB.

Question 19

If a system is to follow arbitrary inputs accurately the bandwidth should be

Accepted Answer

Arbitrary inputs require large bandwidth.

Question 20

For the circuit in the given figure,

Accepted Answer

.

Automatic Control Systems Questions