Explore topic-wise MCQs in Control Systems.

This section includes 8 Mcqs, each offering curated multiple-choice questions to sharpen your Control Systems knowledge and support exam preparation. Choose a topic below to get started.

1.

For the signal flow Graph shown in the figure, the value of \(\frac{{{\rm{C}}\left( {\rm{s}} \right)}}{{{\rm{R}}\left( {\rm{s}} \right)}}\) is

A. \(\frac{{{{\rm{G}}_1}{{\rm{G}}_2}{{\rm{G}}_3}{{\rm{G}}_4}}}{{1 - {{\rm{G}}_1}{{\rm{G}}_2}{{\rm{H}}_1} - {{\rm{G}}_3}{{\rm{G}}_4}{{\rm{H}}_2} - {{\rm{G}}_2}{{\rm{G}}_3}{{\rm{H}}_3} + {{\rm{G}}_1}{{\rm{G}}_2}{{\rm{G}}_3}{{\rm{G}}_4}{{\rm{H}}_1}{{\rm{H}}_2}}}\)
B. \(\frac{{{{\rm{G}}_1}{{\rm{G}}_2}{{\rm{G}}_3}{{\rm{G}}_4}}}{{1 + {{\rm{G}}_1}{{\rm{G}}_2}{{\rm{H}}_1} + {{\rm{G}}_3}{{\rm{G}}_4}{{\rm{H}}_2} + {{\rm{G}}_2}{{\rm{G}}_3}{{\rm{H}}_3} + {{\rm{G}}_1}{{\rm{G}}_2}{{\rm{G}}_3}{{\rm{G}}_4}{{\rm{H}}_1}{{\rm{H}}_2}}}\)
C. \(\frac{1}{{1 + {{\rm{G}}_1}{{\rm{G}}_2}{{\rm{H}}_1} + {{\rm{G}}_3}{{\rm{G}}_4}{{\rm{H}}_2} + {{\rm{G}}_2}{{\rm{G}}_3}{{\rm{H}}_3} + {{\rm{G}}_1}{{\rm{G}}_2}{{\rm{G}}_3}{{\rm{G}}_4}{{\rm{H}}_1}{{\rm{H}}_2}}}\)
D. \(\frac{1}{{1 - {{\rm{G}}_1}{{\rm{G}}_2}{{\rm{H}}_1} - {{\rm{G}}_3}{{\rm{G}}_4}{{\rm{H}}_2} - {{\rm{G}}_2}{{\rm{G}}_3}{{\rm{H}}_3} + {{\rm{G}}_1}{{\rm{G}}_2}{{\rm{G}}_3}{{\rm{G}}_4}{{\rm{H}}_1}{{\rm{H}}_2}}}\)
Answer» C. \(\frac{1}{{1 + {{\rm{G}}_1}{{\rm{G}}_2}{{\rm{H}}_1} + {{\rm{G}}_3}{{\rm{G}}_4}{{\rm{H}}_2} + {{\rm{G}}_2}{{\rm{G}}_3}{{\rm{H}}_3} + {{\rm{G}}_1}{{\rm{G}}_2}{{\rm{G}}_3}{{\rm{G}}_4}{{\rm{H}}_1}{{\rm{H}}_2}}}\)
Discussion
2.

In the signal flow graph of figure given below, the gain C/R will be

A. 11/9
B. 22/15
C. 24/23
D. 44/23
Answer» E.
Discussion
3.

Find the transfer function \(\frac{{Y\left( s \right)}}{{X\left( s \right)}}\) of the system given below

A. \(\frac{{{G_1}}}{{1 - H{G_1}}} + \frac{{{G_2}}}{{1 - H{G_2}}}\)
B. \(\frac{{{G_1}}}{{1 + H{G_1}}} + \frac{{{G_2}}}{{1 + H{G_2}}}\)
C. \(\frac{{{G_1} + {G_2}}}{{1 + H\left( {{G_1} + {G_2}} \right)}}\)
D. \(\frac{{{G_1} + {G_2}}}{{1 - H\left( {{G_1} + {G_2}} \right)}}\)
Answer» D. \(\frac{{{G_1} + {G_2}}}{{1 - H\left( {{G_1} + {G_2}} \right)}}\)
Discussion
4.

For the signal – flow graph shown in the figure, which one of the following expression is equal to the transfer function \({\left. {\begin{array}{*{20}{c}} {Y\left( s \right)}\\ {\overline {{X_2}\left( s \right)} } \end{array}} \right|_{{X_1}\left( s \right) = 0}}?\)

A. \(\frac{{{G_1}}}{{1 + {G_2}\left( {1 + {G_1}} \right)}}\)
B. \(\frac{{{G_2}}}{{1 + {G_1}\left( {1 + {G_2}} \right)}}\)
C. \(\frac{{{G_1}}}{{1 + {G_1}{G_2}}}\)
D. \(\frac{{{G_2}}}{{1 + {G_1}{G_2}}}\)
Answer» C. \(\frac{{{G_1}}}{{1 + {G_1}{G_2}}}\)
Discussion
5.

In the system whose signal flow graph is shown in the figure, U1(s) and U2(s) are inputs. The transfer function \(\frac{{Y\left( s \right)}}{{{U_1}\left( s \right)}}\) is

A. \(\frac{{{k_1}}}{{JL{s^2} + JRs + {k_1}{k_2}}}\)
B. \(\frac{{{k_1}}}{{JL{s^2} - JRs - {k_1}{k_2}}}\)
C. \(\frac{{{k_1} - {U_2}\left( {R + sL} \right)}}{{JL{s^2} + \left( {JR - {U_2}L} \right)s + {k_1}{k_2} - {U_2}R}}\)
D. \(\frac{{{k_1} - {U_2}\left( {sL - R} \right)}}{{JL{s^2} - \left( {JR + {U_2}L} \right)s - {k_1}{k_2} + {U_2}R}}\)
Answer» B. \(\frac{{{k_1}}}{{JL{s^2} - JRs - {k_1}{k_2}}}\)
Discussion
6.

Consider the following block diagramTransfer function \(\frac{{C\left( s \right)}}{{R\left( s \right)}}\)is

A. \(\frac{{{G_1}{G_2}}}{{1 + {G_1}{G_2}}}\)
B. G1G2 + G1 + 1
C. G1G2 + G2 + 1
D. \(\frac{{{G_1}}}{{1 + {G_1}{G_2}}}\)
Answer» D. \(\frac{{{G_1}}}{{1 + {G_1}{G_2}}}\)
Discussion
7.

Calculate the transfer function of the following system.

A. \(\frac{{{G_a}{G_b}}}{{1 + {G_a}{H_a} + {G_b}{H_b} + {G_a}{G_b}{H_a}{H_b}}}\)
B. \(\frac{{{G_a}{G_b}}}{{1 - {G_a}{H_a} - {G_b}{H_b} + {G_a}{G_b} + {G_a}{G_b}{H_a}{H_b}}}\)
C. \(\frac{{{G_a}{G_b}}}{{1 + {G_a}{G_b} + {H_b}{H_a}}}\)
D. \(\frac{{{G_a}{G_b}}}{{1 + {G_a}{G_b}{H_b} + {G_b}{H_a}}}\)
Answer» B. \(\frac{{{G_a}{G_b}}}{{1 - {G_a}{H_a} - {G_b}{H_b} + {G_a}{G_b} + {G_a}{G_b}{H_a}{H_b}}}\)
Discussion
8.

By performing cascading and / or summing / differencing operations using transfer function blocks G1 (s) and G2 (s), one CANNOT realize a transfer function of the form

A. \({{\rm{G}}_1}\left( {\rm{s}} \right){{\rm{G}}_2}\left( {\rm{s}} \right)\)
B. \(\frac{{{{\rm{G}}_1}\left( {\rm{s}} \right)}}{{{{\rm{G}}_2}\left( {\rm{s}} \right)}}{\rm{}}\)
C. \({{\rm{G}}_1}\left( {\rm{s}} \right)\left( {\frac{1}{{{{\rm{G}}_1}\left( {\rm{s}} \right)}} + {{\rm{G}}_2}\left( {\rm{s}} \right)} \right)\)
D. \({{\rm{G}}_1}\left( {\rm{s}} \right)\left( {\frac{1}{{{{\rm{G}}_1}\left( {\rm{s}} \right)}} - {{\rm{G}}_2}\left( {\rm{s}} \right)} \right)\)
Answer» C. \({{\rm{G}}_1}\left( {\rm{s}} \right)\left( {\frac{1}{{{{\rm{G}}_1}\left( {\rm{s}} \right)}} + {{\rm{G}}_2}\left( {\rm{s}} \right)} \right)\)
Discussion