With reference to street - lighting, how do sodium lamps differ from LED lamps?1. Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps.2. As street -lights, sodium lamps have a longer lifespan than LED lamps.3. The spectrum of visible light from sodium lamps is almost monochromatic while LED lamps offer significant colour advantages in street lighting.Select the correct answer using the code given below.
✓ Correct answer: c) 1 and 3 only
ExplanationStatement 1 is correct: Sodium Lamps emit light omnidirectionally (360 degrees), necessitating the use of reflectors to direct light toward the desired area.LED Lamps emit light directionally (typically around 180 degrees), allowing for more efficient illumination with minimal light loss.Statement 2 is incorrect: Sodium Lamps have a shorter operational lifespan compared to LEDs.LED Lamps offer a longer lifespan, often exceeding that of sodium lamps, leading to reduced maintenance and replacement costs.Statement 3 is correct: Sodium Lamps produce a nearly monochromatic light, resulting in poor color rendering and making it difficult to distinguish colors under their illumination.LED Lamps provide a broad spectrum of visible light, offering superior color rendering and enhancing visibility and safety in street lighting applications.159
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