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Saturday, 10 October

NEET UG 2018 · Physics · Question 15

NEET 2018 Physics, question 15

Question 15 of the NEET 2018 paper (code AA) is a Physics question from Semiconductor Electronics: Materials, Devices and Simple Circuits. Its idea, Bipolar Junction Transistor, was asked 3 times, in 2017, 2018 and 2020, across NEET 2017–2026. The CBSE official answer key gives option 4.

Updated 2026-10-08

Q15 · Physics

In the circuit shown in the figure, the input voltage ViV_i is 20 V, VBE=0V_{BE} = 0 and VCE=0V_{CE} = 0. The values of IBI_B, ICI_C and β\beta are given by

The figure, described in words

npn transistor CE circuit: Vi through R_B = 500 kΩ to base; collector to 20 V through R_C = 4 kΩ; emitter grounded.

  1. 1IB=20 μAI_B = 20\ \mu A, IC=5I_C = 5 mA, β=250\beta = 250
  2. 2IB=25 μAI_B = 25\ \mu A, IC=5I_C = 5 mA, β=200\beta = 200
  3. 3IB=40 μAI_B = 40\ \mu A, IC=10I_C = 10 mA, β=250\beta = 250
  4. 4IB=40 μAI_B = 40\ \mu A, IC=5I_C = 5 mA, β=125\beta = 125Official answer

Official answer: option 4 · CBSE official answer key

Same idea

Bipolar Junction Transistor, in other papers

NEET asked this idea 3 times, in 2017, 2018 and 2020. The other 2 questions below.

  • 2020 Q156For transistor action, which of the following statements is correct ?One-line MCQ · Easy
  • 2017 Q21In a common emitter transistor amplifier the audio signal voltage across the collector is 3 V. The resistance of collector is 3 kΩ\Omega.…Numerical · Medium

Bipolar Junction Transistor: every question and how it was framed

The chapter

Semiconductor Electronics: Materials, Devices and Simple Circuits in ten years of NEET

27 questions from 2017–2026, asked in 10 of 10 papers, about 2.6 a paper. Semiconductor Devices alone had 17.

Chapter analysisStudy this chapterPractise this chapter

Semiconductor Electronics: Materials, Devices and Simple Circuits: questions per paper

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