Answer the Below Question with Proper Explanation only. Without explanation I ca
ID: 2988343 • Letter: A
Question
Answer the Below Question with Proper Explanation only. Without explanation I cant justify the answer and I wont provide the points.
Assertion (A):The transient performance of a feedback control system is normally analyzed by using a unit-step function as the reference input.
Reason (R) :Unit step function is the most common input found in practice.
Assertion (A):Strain gauge is an active transducer.
Reason (R) :Strain gauge converts mechanical displacement into change of resistance.
Assertion (A):In a quartz crystal ,at resonance the phase shift between output and input is zero.
Reason (R) :Crystal oscillators provide an extremely stable and precise output frequency.
Explanation / Answer
1. Thevenin's theorem is used find equivalent voltag esource in series with equivalent resistance of a linear bilateral circuit having multiple sources and resistances/ impedances. This can be applied both for D.C voltgaes and A.C voltages.
So, answer is (3), A is TRUE, R is FALSE
2. In the normal operation of BJT, it will operate in Active region in which the emitter diode is Forward biased and collector diode is Reverse biased.
Class A operation can only be obtained when the transistor spends its entire time in the active mode, never reaching either cutoff or saturation.
So, answer is (4), A is FALSE, R is TRUE
3. Helical antennas have long been popular in applications from VHF to microwaves requiring circular polarization, since they have the unique property of naturally providing circularly polarized radiation.
reflection from the parabolic reflector reverses the sense of circular polarization, so that the reflection coming back into the horn will appear at the other port and reduce the isolation.
So, the answer is (2) Both (A) and (R) are true, but (R) is not the Correct explanation of (A).