The amplifier circuit shown below uses a silicon transistor. The capacitors Cc a

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Question
The amplifier circuit shown below uses a silicon transistor. The capacitors C_c and C_E can be assumed to be short at signal frequency and the effect of output resistance r₀ can be ignored. If C_E is disconnected from the circuit, which one of the following statements is TRUE?
Options
A. The input resistance R_i increases and the magnitude of voltage gain A_v decreases
B. The input resistance R_i decreases and the magnitude of voltage gain A_v decreases
C. Both input resistance R_i and the magnitude of voltage gain A_v decrease
D. Both input resistance R_i and the magnitude of voltage gain A_v increase

Correct Answer

The input resistance R_i increases and the magnitude of voltage gain A_v decreases

Explanation

Given circuit after removing C_E will behave as current-series feedback.

Overall voltage gain will decrease as feedback signal comes into picture and since it is current-series feedback, input impedance increases.

More questions

2. In a stop-and-wait ARQ system, the transmitting terminal
Options
A. waits for positive or negative acknowled-gement from the receiving terminal after sending a block
B. sends another block if positive acknowledge is received through ACK character
C. resends the previous block if negative acknowledgement is received through a NAK character
D. does not wait for acknowledgement after sending a block

3. In a bipolar transistor the barrier potential
Options
A. 0
B. a total of 0.7 V
C. 0.7 V across each depletion layer
D. 0.35 V

8. A single phase step up cycloconverter changes 50 Hz to 100 Hz. Then one half wave of input will give rise to
Options
A. one half wave of output
B. one full wave of output
C. two full waves of output
D. either (b) or (c)

9. Which of the following is true about an impulse voltage?
Options
A. It is a unidirectional voltage
B. Chopped impulse flashover does not occur
C. Time taken to rise is equal to time taken to fall
D. RMS value is always less than 50% of average value

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