# Hybrid Equivalent Model MCQ’s

This set of Analog Electronic Circuits Multiple Choice Questions & Answers (MCQs) focuses on “Hybrid Equivalent Model.

1. Consider the following circuit. __________ provides DC isolation. _____________ prevents a decrease in voltage gain. _____________ is used to control the bandwidth.

a) C3, C1, C4
b) C4, C1, C2
c) C2, C3, C2
d) C4, C3, C2

2. Given hfe = 60, hie=1000Ω, hoe = 20μ Ω, hre = 2 * 10-4. Find the current gain of the BJT, correct up to two decimal points.

a) – 58.44
b) -59.21
c) – 60.10
d) – 60.00

3. Which of the following statement is incorrect?
a) Output of CE amplifier is out of phase with respect to its input
b) CC amplifier is a voltage buffer
c) CB amplifier is a voltage buffer
d) CE amplifier is used as an audio (low frequency) amplifier

4. Consider the circuit. Given hfe = 50, hie = 1200Ω. Find voltage gain.

a) – 278
b) -277.9
c) – 300
d) – 280

5. Consider the following circuit, where source current = 10mA, hfe = 50, hie = 1100Ω, then for the transistor circuit, find output resistance RO and input resistance RI.

a) RO = 0, RI = 21Ω
b) RO = ∞, RI = 0Ω
c) RO = ∞, RI = 21Ω
d) RO = 10, RI = 21Ω

6. Consider its input resistance to be R1. Now, the bypass capacitor is attached, so that the new input resistance is R2. Given that hie = 1000Ω and hfe = 50, find R1-R2.

a) 112.2Ω
b) 0Ω
c) 110Ω
d) 200Ω

7. Given that IB = 5mA and hfe = 55, find load current.

a) 28mA
b) 280mA
c) 2.5A
d) 2A

8. For the given circuit, input resistance RI = 20Ω, hfe = 50. Output resistance = ∞. Find the new values of input and output resistance, if a base resistance of 2kΩ is added to the circuit.

a) RI = 20Ω, RO = ∞
b) RI = 20Ω, RO = 2kΩ
c) RI = 59Ω, RO = ∞
d) RI = 59Ω, RO = 2kΩ

9. Given that for a transistor, hie = 1100Ω, hfe = 50, hre = 2*10-4 and hoe = 2μΩ-1. Find CB h-parameters.
a) hfb = 1, hib = 22, hob = 3μΩ-1, hrb = -1.5×10-4
b) hfb = -0.98, hib = -21.56, hob = 0.03μΩ-1, hrb = 1.5×10-4
c) hfb = -0.98, hib = 21.56, hob = 0.03μΩ-1, hrb = -1.5×10-4
d) hfb = 1, hib = -21.56, hob = 0.03μΩ-1, hrb = -2×10-4

10. If source resistance in an amplifier circuit is zero, then voltage gain (output to input voltage ratio) and source voltage gain (output to source voltage ratio) are the same.
a) True
b) False