Three photodiodes `D_1 , D_2 ` and `D_3` are made of semiconductors having band gaps of ` 2.5 eV , 2 eV` and 3 eV , respectively . Which one will be able to detect light of wavelength ` 6000 Å ` ?
Text Solution
Verified by Experts
Energy of the incident photon, `E=(hc)/lambda=((6.6xx10^(-34))xx(3xx10^(8)))/((6xx10^(-7))xx1.6xx10^(-19))=2.06eV` The incident radiation can be detected by a photodiode if energy of incident radiation photon is greater than the band gap. This is true for `D_(2)(=2eV)`. Therefore, only `D_(2)` will detect these radiations.
Topper's Solved these Questions
ELECTRONIC DEVICES
PRADEEP|Exercise SAMPLE PROBLEM|2 Videos
ELECTRONIC DEVICES
PRADEEP|Exercise CONCEPTUAL PROBLEMS|1 Videos
ELECTROMAGNETIC WAVES
PRADEEP|Exercise II Focus multiple choice question|5 Videos
ELECTROSTATICS
PRADEEP|Exercise ASSERTION-REASON TYPE QUESTIONS|2 Videos
Similar Questions
Explore conceptually related problems
(i) three photodiodes D_(1),D_(2) and D_(3) are made of semiconductors ahving band gaps of 2.5 eV 2eV and 3eV respecitvely which of them will not be able to detect light of wavelenghth 600nm (ii) why phtoodiodes are required to operate in revese bias explain
Two metals a and b have work function 5 eV and 7 eV , respectively . Which metal has a lower threshold wavelength ?
Work functions of caesium and lead are 2.14 eV and 4.25 eV respectively. Which of the two has a higher threshold wavelength ?
Work functions for metals A and B are 2 eV and 4 eV respectively. Which metal has a lower threshold wavelength and why ?
Two metals A and B have work function 2 eV and 4 eV , respectively . Which metal has a lower threshold wavelength for photoelectric effect ?
