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Consider the following statements:
A. The junction area of solar cell is made very narrow compared to a photo diode.
B. Solar cells are not connected with any external bias.
C. LED is made of lightly doped p-n junction.
D. Increase of forward current results in continuous increase of LED light intensity.
E. LEDs have to be connected in forward bias for emission of light.
Which of the following is correct?
- B, D, E Only
- A, C Only
- A, C, E Only
- B, E Only
Correct answer: B, E Only
Solution
Statements B and E are correct because solar cells operate without external bias and LEDs must be connected in forward bias to emit light. The other statements either misrepresent the characteristics of solar cells or LEDs.
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