## Sunday, 29 December 2013

### ELECTRIC CIRCUITS & ANALYSIS

ELECTRIC CIRCUITS & ANALYSIS

1. What is the type of capacitor used in RC coupled amplifier for a) coupling two phases b) by pass emitter
Ans: Generally electrolytic capacitors are used.
2. List out the different types of biasing.
Ans:
·         Voltage divider bias
·         Base bias
·         Emitter feed back bias
·         Collector feedback bias
3. Define current amplification factor?
Ans: It is defined as the ratio of change in output current to the change in input current at  constant other side voltage.
4. What is biasing?
Ans: To use the transistor in any application it is necessary to provide sufficient voltage and current to operate the transistor. This is called biasing.
5. What is an amplifier?
Ans: An amplifier is a device which produces a large electrical output of similar             characteristics to that of the input parameters.
6. What is feed back?
Ans: It is the process of injecting some energy from the output and then returns it back to the input.
7. What is a tuned amplifier?
Ans: The amplifier with a circuit that is capable of amplifying a signal over a narrow band of frequencies are called tuned amplifiers.
8. The ratio of reactance to resistance is Q factor.
9. What is Oscillator circuit?
Ans: A circuit with an active device is used to produce an alternating current is called an oscillator circuit.

10. A Multivibrator has two states. They may be either stable or quasi stable state.
11. Astable Multivibrator has two quasi stable states.
12. A monostable Multivibrator having one stable state and another quasi stable state.
13. Positive feedback is the type of feedback used in an op-amp Schmitt trigger.
14. F = 1 / (2πRC) is the expression for the frequency of oscillations in an op-amp sine                wave oscillator.
15. What is meant by voltage follower?
Ans: If the output voltage of an op-amp follows the input i.e., if the output voltage is equal            to the input voltage it is called as a voltage follower.
16. The operational amplifier is a multi-terminal device, which is quite complex internally.

17. Positive feedback ,Negative feedback are the types of feed back.