The electrical conductivity of a semiconductor increases when a radiation of wavelength shorter than 1000 nm is incident on it. The band gap of the semiconductor is A- 2.4 eV B- 2.2 eV C- 1.2 eV D- 0.8 eV
Question
The electrical conductivity of a semiconductor increases when a radiation of wavelength shorter than 1000 nm is incident on it. The band gap of the semiconductor is A- 2.4 eV B- 2.2 eV C- 1.2 eV D- 0.8 eV
Solution
The energy of the radiation can be calculated using the formula:
E = hc/λ
where: E is the energy, h is Planck's constant (6.626 x 10^-34 Js), c is the speed of light (3 x 10^8 m/s), and λ is the wavelength.
First, convert the wavelength from nm to m:
1000 nm = 1000 x 10^-9 m = 1 x 10^-6 m
Then, substitute the values into the formula:
E = (6.626 x 10^-34 Js)(3 x 10^8 m/s) / 1 x 10^-6 m E = 1.987 x 10^-19 J
To convert this energy to electron volts (eV), use the conversion factor 1 eV = 1.6 x 10^-19 J:
E = 1.987 x 10^-19 J * (1 eV / 1.6 x 10^-19 J) E = 1.24 eV
Therefore, the band gap of the semiconductor is closest to 1.2 eV, so the answer is C- 1.2 eV.
Similar Questions
What should be the approximate band gap of the semiconductors to be used as solar cell materials?a.1.3 eVb.0.08 eVc.0.45 eV
In a photodiode, the conductivity increases when the material is exposed to light. It is found that conductivity changes only if the wavelength is less than 600 nm. What is the bandgap?
The effect of increase in temperature on the number of electrons in conduction band (ne) and resistance of a semiconductor will be as:Both ne and resistance decreaseBoth ne and resistance increasene increases, resistance decreasesne decreases, resistance increases
Which of the following is known as indirect band gap semiconductorsSelect one:a. Goldb. Carbonc.Germaniumd. Nickel
In an intrinsic semiconductor, the Fermi levelSelect one:a. May be anywhere in the forbidden energy gapb. Is near the valence band.c. Is near the conduction bandd. Lies at the centre of forbidden energy gap
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.