Question:
Which one of the following statements is 'WRONG' regarding LED?
Which one of the following statements is 'WRONG' regarding LED?
Show Hint
The brightness of an LED can be controlled through the current.
Updated On: Oct 1, 2026
- LED's have long lifetime if properly manufactured.
- Colours produced by LED's do not fade out.
- LED's are energy efficient.
- Brightness of light emitted by LED cannot be controlled.
Show Solution
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The Correct Option is D
Solution and Explanation
Step 1: Understanding the Concept:
A light emitting diode (LED) is a forward biased p-n junction that gives out light. The brightness depends on the forward current.
Step 2: Key Formula or Approach:
Check each statement against the known properties of an LED.
Step 3: Detailed Explanation:
A: properly made LEDs last a long time. True.
B: the colour of an LED is fixed by the semiconductor material, so it does not fade. True.
C: LEDs turn most of the electrical energy into light, so they are efficient. True.
D: says that the brightness cannot be controlled. This is wrong, since changing the current changes the brightness, which is why LEDs can be dimmed.
Final Answer:
The wrong statement is D, option (D). \[ \boxed{\text{D}} \]
A light emitting diode (LED) is a forward biased p-n junction that gives out light. The brightness depends on the forward current.
Step 2: Key Formula or Approach:
Check each statement against the known properties of an LED.
Step 3: Detailed Explanation:
A: properly made LEDs last a long time. True.
B: the colour of an LED is fixed by the semiconductor material, so it does not fade. True.
C: LEDs turn most of the electrical energy into light, so they are efficient. True.
D: says that the brightness cannot be controlled. This is wrong, since changing the current changes the brightness, which is why LEDs can be dimmed.
Final Answer:
The wrong statement is D, option (D). \[ \boxed{\text{D}} \]
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