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Read the following text and answer the f...

Read the following text and answer the following questions on the basis of the same:
Light Emitting Diode:
It is a heavily doped p-n junction which under forward bias emits spontaneous radiation. The diode is encapsulated with a transparent cover so that emitted light can come out. When the diode is forward biased, electrons are sent from n `to` p (where they are minority carriers) and holes are sent from p`to`n(where they are minority carriers). At the junction boundary, the concentration of minority carriers increases as compared to the equilibrium concentration (i.e., when there is no bias).
Thus at the junction boundary on either side of the junction, excess minority carriers are there which recombine with majority carriers near the junction. On recombination, the energy is released in the form of photons. Photons with energy equal to or slightly less than the band gap are emitted. When the forward current of the diode is small, the intensity of light emitted is small. As the forward current increases, intensity of light increases and reaches a maximum. Further increase in the forward current results in decrease of light intensity. LED's are biased such that the light emitting efficiency is maximum.
The V-I characteristics of a LED is similar to that of a Si junction diode. But, the threshold voltages are much higher and slightly different for each colour. The reverse breakdown voltages of LED's are very low, typically around 5 V. So care should be taken that high reverse voltages do not appear across them. LED's that can emit red, yellow, orange, green and blue light are commercially available.
The reverse breakdown voltages of LED's are:

A

very low and typically around 0.5 V.

B

very low and typically around 5 V.

C

very high and typically around 50 V.

D

very low and typically around 0.05 V.

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To answer the question regarding the reverse breakdown voltages of LEDs based on the provided text, we will follow these steps: ### Step-by-Step Solution: 1. **Identify the Topic**: We need to focus on the reverse breakdown voltage of LEDs as mentioned in the text. 2. **Read the Relevant Section**: The text states: "The reverse breakdown voltages of LED's are very low, typically around 5 V." This is the key information we need. 3. **Analyze the Options**: The options given are: - A) Very low and typically around 0.5V - B) Very low and typically around 5V - C) Very high and typically around 50V - D) Very low and typically around 0.05V 4. **Match the Information**: From the text, we see that the reverse breakdown voltage is described as "very low and typically around 5V." This matches option B. 5. **Eliminate Incorrect Options**: - Option A (0.5V) is incorrect as the text specifies 5V. - Option C (50V) is incorrect as the text states that the breakdown voltage is very low. - Option D (0.05V) is also incorrect for the same reason. 6. **Conclude the Answer**: Based on the analysis, the correct answer is: - **B) Very low and typically around 5V** ### Final Answer: The reverse breakdown voltages of LEDs are very low and typically around 5V. ---

To answer the question regarding the reverse breakdown voltages of LEDs based on the provided text, we will follow these steps: ### Step-by-Step Solution: 1. **Identify the Topic**: We need to focus on the reverse breakdown voltage of LEDs as mentioned in the text. 2. **Read the Relevant Section**: The text states: "The reverse breakdown voltages of LED's are very low, typically around 5 V." This is the key information we need. ...
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Read the following text and answer the following questions on the basis of the same: Light Emitting Diode: It is a heavily doped p-n junction which under forward bias emits spontaneous radiation. The diode is encapsulated with a transparent cover so that emitted light can come out. When the diode is forward biased, electrons are sent from n to p (where they are minority carriers) and holes are sent from p to n(where they are minority carriers). At the junction boundary, the concentration of minority carriers increases as compared to the equilibrium concentration (i.e., when there is no bias). Thus at the junction boundary on either side of the junction, excess minority carriers are there which recombine with majority carriers near the junction. On recombination, the energy is released in the form of photons. Photons with energy equal to or slightly less than the band gap are emitted. When the forward current of the diode is small, the intensity of light emitted is small. As the forward current increases, intensity of light increases and reaches a maximum. Further increase in the forward current results in decrease of light intensity. LED's are biased such that the light emitting efficiency is maximum. The V-I characteristics of a LED is similar to that of a Si junction diode. But, the threshold voltages are much higher and slightly different for each colour. The reverse breakdown voltages of LED's are very low, typically around 5 V. So care should be taken that high reverse voltages do not appear across them. LED's that can emit red, yellow, orange, green and blue light are commercially available. LED emits light:

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When p-n junction diode is forward biased then

When p- n junction diode is forward baised them

For making p-n junction diode forward biased: