The energy of a photon (λ = 589 nm) equals the band gap of a semiconducting material. The minimum energy required to create a hole-electron pair is:
Correct answer: B. 2.1 eV
- A. 4.2 eV
- B. 2.1 eV
- C. 1.2 eV
- D. 0.98 eV
Explanation
Photon energy E = hc/λ = 1240/589 ≈ 2.1 eV, which matches the band gap energy required to create a hole-electron pair.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Electronics
A p-n junction forms when p-type and n-type semiconductor regions meet, creating a depletion layer, barrier potential and rectifying action. The work covers forward and reverse bias, junction current, diode characteristics, and how a diode converts alternating current into pulsating direct current through half-wave and full-wave rectification.
Practise Electronics
660 free Electronics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Electronics questions
When a P-N junction diode is forward biased, then:
The valence band and conduction band of a solid overlap at low temperature, the solid may be:
A type of metals containing alloys, ceramics etc., when heated their temperature reaches to a state called Transition temperature state and their resistance reaches to zero. These types of metals are called
The valence of an impurity added to a germanium crystal to convert it into a P-type semiconductor is:
If Np and Ne are the numbers of holes and conduction electrons in an extrinsic semiconductor, then:
A semiconducting device connected in series with a cell and resistor indicates some current in the circuit. If the polarity of the battery is reversed, the current almost reduces to zero. The device may be: