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How do Mercury vapour lamps differ from LED lamps? 1. LEDs have a lower radiance than mercury arc lamps.  2. Mercury lamps are eco-friendly as they require low voltages than LED lamps to operate. Select the correct answer using the code given below.

How do Mercury vapour lamps differ from LED lamps? 1. LEDs have a lower radiance than mercury arc lamps.  2. Mercury lamps are eco-friendly as they require low voltages than LED lamps to operate. Select the correct answer using the code given below. Correct Answer 1 only

The correct answer is ​1 only.

Key Points

  • Mercury vapour lamps  are bright, long-lasting light sources that are often used to light large areas such as streets, gyms, sports arenas, banks, or stores.
    • The bulbs have an inner quartz tube containing mercury vapour discharge.
    • This is enclosed by an outer glass bulb that filters out harmful short-wavelength ultraviolet (UV) radiation.
    • Mercury vapour lamps were the first high-intensity discharge lamps to be commercially available for a wide variety of lighting applications.
  • An LED lamp or LED light bulb is an electric light that produces light using light-emitting diodes (LEDs).
    • LED lamps are significantly more energy-efficient than equivalent incandescent lamps and can be significantly more efficient than most fluorescent lamps.
LED lamps Mercury Vapor lamps
LEDs have a lower radiance than mercury arc lamps. Mercury lamps require high voltages to operate and radiate toward the UV emission a lot of heat
LEDs use less energy as they don’t need to warm up or cool down, unlike mercury arc lamps. Mercury vapour lamps require time to warm up prior to use. They are omnidirectional and rely on heat to help produce lighting. 
LEDs are energy efficient and eco friendly as their applied voltage is low Mercury and metal halide used in Mercury Vapor lamps are dangerous for the environment. 

Hence only statement 1 is correct.

Related Questions

With reference to street-lighting, how do Mercury vapour lamps differ from LED lamps? 1. Mercury vapour lamps use a fraction of the energy used in the case of LED lamps. 2. LEDs have a lower radiance than mercury arc lamps.  3. Mercury lamps are eco-friendly as they require low voltages than LED lamps to operate. Select the correct answer using the code given below.
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