A p-n photodiode is fabricated from a semiconductor with a band gap of 2.5 eV.

⇦

⇨

A p-n photodiode is fabricated from a semiconductor with a band gap of 2.5 eV. It can be detect a signal of wavelength

Options

(a) 4000 nm
(b) 6000 nm
(c) 4000Å
(d) 6000Å

Correct Answer:

4000Å

Explanation:

λₘₐₓ = hc / E
= 6.6 x 10⁻³⁴ x 3 x 10⁸ / 2.5 x 1.6 x 10⁻¹⁹ = 5000Å
The wavelength detected by photodiode should be less than λₘₐₓ. Hence it can detect a signal of wavelength 4000Å.

Related Questions:

1. A circular coil of radius 10cm and 100 turns carries a current 1 A.
2. The wavelength λₑ of an electron and λₚ of a photon are of same energy E are related by
3. When there is no heat change from surroundings in a system, then the process
4. In which of the processes, does the internal energy of the system remain constant?
5. Four identical rods are joined to from a square. If the temperature difference

Topics: Electronic Devices (124)
Subject: Physics (2479)

---

Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score

18000+ students are using NEETLab to improve their score. What about you?

Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.

---

Share this page with your friends