NEET Physics / AI question bank / NCERT Class 12 / Electronic Devices
Semiconductor Electronics: Materials, Devices and Simple Circuits: NEET questions with solutions
NEET tests band gaps of metals, semiconductors and insulators, intrinsic carriers and the law of mass action nₑnₕ = nᵢ², n-type and p-type doping, how a p-n junction forms its depletion layer and barrier, forward and reverse bias, dynamic resistance from a V–I curve, diodes in simple circuits, and half-wave and full-wave rectification. Marks are lost by thinking doped crystals are charged, by taking static V/I for dynamic resistance, and by forgetting that a full-wave output ripples at twice the mains frequency.
Also called: semiconductors · p-n junction diode · logic gates · rectifiers
Questions
10 questions / answers after you pick
- Q1A pure silicon crystal is doped with a small amount of arsenic, a group-15 element. What kind of semiconductor results, and what are its…
Extrinsic semiconductorEasySingle correct
- Q2Diamond (carbon), silicon and germanium all have the same crystal structure with four valence electrons per atom. Which ordering of their…
Classification of metals, conductors and semiconductorsEasySingle correct
- Q3A silicon sample at a temperature where nᵢ = 2.4 × 10¹⁹ m⁻³ is doped with donors at a concentration of 4.0 × 10²² m⁻³. Taking every donor as…
Extrinsic semiconductorMediumSingle correct
- Q4A full-wave rectifier built from two diodes and a centre-tapped transformer is fed from a 60 Hz AC supply. What is the fundamental frequency…
Application of junction diode as a rectifierEasySingle correct
- Q5A silicon p-n junction with built-in barrier V₀ is studied first unbiased, then with an external voltage V in forward bias and in reverse…
Semiconductor diodeMediumStatement based
- Q6In a forward-biased silicon diode, the current rises from 10 mA to 20 mA when the voltage across it is increased from 0.70 V to 0.75 V. What…
Semiconductor diodeMediumSingle correct
- Q7A 5.0 V battery feeds two parallel branches. Each branch is a 1.0 kΩ resistor in series with an identical silicon diode (forward drop 0.7…
Semiconductor diodeHardSingle correct
- Q8A silicon wafer (nᵢ = 1.5 × 10¹⁶ m⁻³) is doped with indium, a group-13 element, at a concentration of 2.5 × 10²² m⁻³. Taking every dopant…
Extrinsic semiconductorHardSingle correct
- Q9Match each element in List I with its role or property in List II.
Intrinsic semiconductorMediumMatch the following
- Q10A strip of pure silicon is warmed from room temperature to 100 °C while its resistance is monitored, and the resistance drops. Read the…
Intrinsic semiconductorMediumAssertion–Reason
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