All Exams Test series for 1 year @ ₹349 only
Question

Which of the following type of lamp gives more illumination from low wattage ?

The correct answer is
LED lamp

Lamp Efficiency for Illumination

The question asks which lamp type provides the most light output (illumination) for a low power input (wattage). This is determined by a lamp's luminous efficacy, measured in lumens per watt (lm/W). A higher lm/W rating signifies greater efficiency, meaning more light is produced for less energy consumed.

Analysis of Lamp Types

  • Incandescent Lamps: These are the least efficient, converting a significant portion of energy into heat rather than light. Their luminous efficacy is very low, typically around 10-17 lm/W.
  • Fluorescent Lamps: These offer better efficiency than incandescent lamps. Their luminous efficacy ranges generally from 50-100 lm/W.
  • Compact Fluorescent Lamps (CFLs): These are more energy-efficient versions of fluorescent lamps, with luminous efficacy typically between 60-110 lm/W.
  • LED Lamps: Light Emitting Diodes (LEDs) are currently the most efficient lighting technology widely available. They provide the highest luminous efficacy, often ranging from 80 lm/W up to 150 lm/W and beyond, offering the most illumination for low wattage.

Conclusion

Comparing the luminous efficacy, LED lamps deliver the most illumination for low wattage consumed.

Was this answer helpful?

Important Questions from Illumination

  1. Silicon solar cell has an open circuit voltage NOT equivalent to-

  2. What is the primary function of a choke in a tube light circuit?

  3. Light is produced in electric discharge lamps by

  4. ________ lamps consist of an inner discharge tube and an outer evacuated tube.

  5. A mercury vapor lamp gives ______ light.

Need Expert Advice?

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App