-
০০।
. It is required that response settles to within 2% of final value for a step input. The settling time is
- ক) 20 sec
- খ) 40 sec
- গ) 35 sec
- ঘ) 45 sec
-
০১। A compensating network has
. If it is a phase lag circuit the value of a should be
- ক) 0
- খ) between 0 and 1
- গ) 1
- ঘ) more than 1
-
০২। A compensator has its pole and zero as shown in the given figure
- ক) lag compensator
- খ) lead compensator
- গ) lead-lag compensator
- ঘ) series compensator
- ০৩। A conditionally stable system has
- ক) one phase crossover frequency
- খ) two phase crossover frequencies
- গ) two or more phase crossover frequencies
- ঘ) one or more phase crossover frequencies
- ০৪। A conditionally stable system is stable for the value of gain between two critical values. It is unstable if
- ক) the gain is increased beyond upper critical value
- খ) the gain is decreased below lower critical value
- গ) both (a) and (b)
- ঘ) none of the above
-
০৫। A feedback amplifier has forward gains A1, A2 and feedback factor β as shown in signal flow graph of the given figure. Because of feedback as shown in signal noise ratio at output will
- ক) increase
- খ) decrease
- গ) be unaffected
- ঘ) depend on value of β
- ০৬। A first order element yields almost exact duplication only for constant or slowly varying phenomenon.
- ক) True
- খ) False
- ০৭। A first-order system has a time constant t. For unit ramp input, the steady state error is
- ক) t 2
- খ) t
- গ) t
- ঘ) 1/t
- ০৮। A lag compensator
- ক) speeds up the transient response of the system
- খ) improves steady state behaviour of the system
- গ) improves steady state behaviour and speeds up the transient response of the system
- ঘ) improves steady state behaviour and preserves the transient response of the system
- ০৯। A lag compensator is essentially a
- ক) low pass filter
- খ) high pass filter
- গ) band pass filter
- ঘ) either (a) or (b)
- ১০। A lag compensator provides attenuation in
- ক) very low frequency range
- খ) low frequency range
- গ) high frequency range
- ঘ) none of the above
- ১১। A lead compensator
- ক) speeds up the transient response
- খ) increases the stability margin
- গ) increases the stability margin and speeds up the transient-response.
- ঘ) none of the above.
- ১২। A lead compensator is basically a
- ক) high pass filter
- খ) low pass filter
- গ) band stop filter
- ঘ) none of the above
- ১৩। A motor is coupled to a load through gear ratio n. If T is the motor torque, Jm and JL are moment of inertia of rotor and load, then torque to inertia ratio referred to motor shaft is
- ক)
- খ)
- গ)
- ঘ)
-
১৪। A negative feedback system has
. The closed loop system is stable for
- ক) K > 20
- খ) 15 < K < 19
- গ) 8 ≤ K ≤ 14
- ঘ) K < 6
-
১৫। A network has
. Then
- ক) it is lead network
- খ) it is lag network
- গ) it is lead network if T1 > T2 and lag network T1 < T2
- ঘ) it is lead network if T1 < T2 and lag network T1 > T2
-
১৬। A phase lead network with
where a < 1, gives maximum phase lead at a frequency equal to
- ক)
- খ)
- গ)
- ঘ)
- ১৭। A proportional controller is basically
- ক) an amplifier with adjustable gain
- খ) an integrating amplifier
- গ) an amplifier with infinite gain
- ঘ) an amplifier with almost zero gain
- ১৮। A second order system exhibits 100% overshoot. The damping ratio is
- ক) 0
- খ) 1
- গ) < 1
- ঘ) > 1
- ১৯। A second order system has damping ratio x and natural frequency ωn. The unit step response is
- ক)
- খ)
- গ)
- ঘ)