# Transition Capacitance MCQ’s

This set of Analog Electronic Circuits Multiple Choice Questions & Answers (MCQs) focuses on “Transition Capacitance”.

1. Which of the following is not known as transition capacitance?
a) Depletion region capacitance
b) Space-Charge capacitance
c) Nominal capacitance
d) Junction capacitance

2. Transition capacitance of a diode is directly proportional to ____________
a) Area of cross section
b) Width of depletion region
c) Reverse voltage applied across the terminals
d) Drift current

3. Which of the following is not known as transition capacitance?
a) Junction capacitance
b) Space-Charge capacitance
c) Diffusion capacitance
d) Barrier capacitance

4. Transition capacitance of a diode is inversely proportional to __________
a) Area of cross section
b) Width of depletion region
c) Relative permittivity
d) Drift current

5. What is the dependence of the transition capacitance on relative permittivity?
a) Inversely proportional to relative permittivity
b) Directly proportional to relative permittivity
c) Independent of relative permittivity
d) Directly proportional to relative permittivity with a degree of 2

6. For a diode the transition capacitance was 15pF. The diode is replaced with another diode of same material with twice cross sectional area. Terminal voltage remains unchanged. The capacitance of new diode is __________
a) 15pF
b) 30pF
c) 60pF
d) 7.5pF

7. As reverse bias voltage increases transition capacitance __________
a) Increases
b) Decreases
c) Doesn’t depend upon voltage
d) Constant

8. For a diode the transition capacitance was 10pF. The depletion width changed from 1µm to 10 µm. All other conditions remain unchanged. The new diode capacitance is __________
a) 5pF
b) 1.414pF
c) 1pF
d) 10pF

9. A diode is replaced with another diode of different material. The ratio of relative permittivity of new material to old is 0.5. The initial capacitance was 20pF, then final capacitance will be __________
a) 15pF
b) 20pF
c) 10pF
d) 2pF

10. Consider two diodes, A is step graded, B is linear graded. Find the ratio of the capacitance of A to B, when the applied voltage in reverse bias is 64V.
a) 0.2
b) 2
c) 0.5
d) 5

11. A diode had a transition capacitance of 1pF and depletion width of 1 µm. The capacitance changes to 10 pF when the depletion width changes. The final depletion width is __________
a) 10 µm
b) 0.1 µm
c) 1 µm
d) 100 µm

12. Consider 2 reverse biased diodes. If the ratio of applied reverse bias voltages is 0.5, find the ratio of transition capacitances of the 2 diodes.
a) 2
b) 4
c) 1.31
d) 2.6

13. The transition capacitance depends on the forward current of the diode.
a) True
b) False

14. Which of these is the odd one in the choices?
a) Transition capacitance
b) Diffusion capacitance
c) Space charge capacitance
d) Depletion layer capacitance

15. Capacitance per unit area at no reverse bias is 2 pF/cm2. For a step graded diode of area 5cm2, what is net capacitance at 99 V reverse bias voltage?
a) 2pF
b) 5pF
c) 0.1pF
d) 1pF