1. Define open and closed loop control systems. Explain difference between time varying and time invariant control system with suitable example.

2. Derive Transfer Function of the following diagram using signal flow graph.

3. Consider characteristic equation, find stability of the system with Routh Hurwitz criterion

  S⁶ + S⁵ + 6s⁴ + 5s³ + 10s² + 5s + 5

4. Determine the stability of the closed-loop transfer function

5. The frequency response of the plant transfer function H(s) may be found by evaluating the following:

                         M = |H(s)|s=jw and Φ = arg |H(s)|_s=jw

Where M is the magnitude and Φ is the phase shift. Find the frequency response assuming the following transfer function.

a) Draw magnitude response in the space provided. Mention the frequency and magnitude on the graph

b) Illustrate the effects of individual pole and zeroes response in the semi log graph  

c) Explain magnitude response of zero

6. Find transfer function using block diagram reduction technique