Which of the following statements is true about LEDs
Which of the following statements is true about LEDs
High operational voltage
Warm-up time is required
Bandwidth of ligth is 4000 A -7000 A
Fast on-off switching
The Correct Option is D
Solution and Explanation
To solve the problem, we need to identify the correct characteristic of LEDs (Light Emitting Diodes) from the given statements.
1. Key Characteristics of LEDs:
- LEDs operate at low voltages and currents, making them energy-efficient.
- They do not require warm-up time; they light up instantly when current flows.
- The emission wavelength of LEDs depends on the semiconductor material used and is typically within a narrow range, not the full 4000–7000 Å (which is the visible light range in general).
- LEDs have very fast response times, allowing for rapid on-off switching.
2. Evaluating the Options:
- "High operational voltage" → Incorrect: LEDs work on low voltage.
- "Warm-up time is required" → Incorrect: LEDs are instant-on devices.
- "Bandwidth of light is 4000 Å – 7000 Å" → Incorrect: Each LED emits in a much narrower wavelength range.
- "Fast on-off switching" → Correct: This is a well-known and highly advantageous property of LEDs, used in digital displays and high-speed communication.
Final Answer:
The true statement about LEDs is: Fast on-off switching.
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Concepts Used:
Wave Optics
- Wave optics are also known as Physical optics which deal with the study of various phenomena such as polarization, interference, diffraction, and other occurrences where ray approximation of geometric optics cannot be done. Thus, the section of optics that deals with the behavior of light and its wave characteristics is known to be wave optics.
- In wave optics, the approximation is carried out by utilizing ray optics for the estimation of the field on a surface. Further, it includes integrating a ray-estimated field over a mirror, lens, or aperture for the calculation of the transmitted or scattered field.
- Wave optics stands as a witness to a famous standoff between two great scientific communities who devoted their lives to understanding the nature of light. Overall, one supports the particle nature of light; the other supports the wave nature.
- Sir Isaac Newton stood as a pre-eminent figure that supported the voice of particle nature of light, he proposed a corpuscular theory which states that “light consists of extremely light and tiny particles, called corpuscles which travel with very high speeds from the source of light to create a sensation of vision by reflecting on the retina of the eye”.