## Physics MCQ on Photodiode for NEET, JEE, Medical and Engineering Exam 2021

MCQ on Photodiode: Previous trends reveal that NEET/JEE aspirants find Physics as the most challenging section amongst the other sections. But most of them fail to decipher the reason behind this. This particularly can be as the candidates taking up this examination are predominantly medical aspirants with their subject of interest being Biology. Also, sections like Physics are more on theories, laws, numerical as opposed to Biology which is more of fact-based, life sciences and comprising of substantial explanations.

In this post we are providing you MCQ on Photodiode, which will be beneficial for you in upcoming NEET, AIIMS, JEE, WBJEE, Medical and Engineering Exams.

## MCQ on Photodiode

Q1. The maximum wavelength of photons that can be detected by a photodiode made by a semiconductor of bandgap 2eV is about _____.
a) 620 nm
b) 700 nm
c) 740 nm
d) 1240 nm

(a) 620 nm

Q2. Compared to a photo-diode, which of the listed advantages and disadvantages would be expected of a phototransistor _____.
a) Faster response and greater sensitivity
b) Faster response and less sensitivity
c) Slower response and greater sensitivity
d) Slower response and less sensitivity

(c) Slower response and greater sensitivity

Q3. Photodiodes operate by absorption of photons or charged particles and generate a flow of current in an external circuit, _____ to the incident power. The light is absorbed _____ with distance and is _____ to the absorption coefficient.
a) Proportional, exponentially, proportional
b) Proportional, logarithmically, inversely proportional
c) Inversely proportional, exponentially, unrelated

(a) Proportional, exponentially, proportional

Q4. In a photodiode, when there is no incident light, the reverse current is almost negligible and is called _____.
a) Zener current
b) Dark current
c) Photocurrent
d) PIN current

(b) Dark current

Q5. The width of the depletion region is _____.
a) Directly proportional to the doping
b) inversely proportional to the doping
c) Independent of doping
d) None of the above

(b) inversely proportional to the doping

Q6. Photodiode is used in the detection of _____.
a) Visible light
b) Invisible light
c) No light
d) Both visible and invisible light

(d) Both visible and invisible light

Q7. When a diode is forward biased, the recombination of free electron and holes produce _____.
b) Heat
c) Light
d) All the above

(d) All the above

Q8. In using a photodiode as a photodetector, it is invariably reverse biased.
a) The power consumption is much reduced compared to reverse biased condition
b) Only when the photodiode is reverse biased the incident photons produce electron-hole pairs
c) Only if the diode is reverse biased light variations can be converted into current variations
d) When photons are incident on the diode, the fractional change in the reverse current is much greater than the fractional change in the forward current

(d) When photons are incident on the diode, the fractional change in the reverse current is much greater than the fractional change in the forward current

Q9. What is the reason phototransistor produces more current than a photodiode?
a) A wider spectrum is accepted by the phototransistor than the photodiode
b) The current produced by photons is amplified by the hfe of the transistor
c) The phototransistor can heavily doped than the photodiode
d) At low light conditions, a photodiode is used.

(c) The phototransistor can heavily doped than the photodiode

Q10. The presence of dark current decreases the sensitivity of the photodiode to light.
a) True
b) False

(a) True