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What is the difference between a CFL and an LED lamp? 1. To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semiconductor material. 2. The average life span of a CFL is much longer than that of an LED lamp. 3. A CFL is less energy-efficient as compared to an LED lamp. Which of the statements given above is/are correct?

What is the difference between a CFL and an LED lamp? 1. To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semiconductor material. 2. The average life span of a CFL is much longer than that of an LED lamp. 3. A CFL is less energy-efficient as compared to an LED lamp. Which of the statements given above is/are correct? Correct Answer 1 and 3 only

The correct answer is 1 and 3 only.

 Key Points

  • LED bulbs are much more efficient than CFL bulbs in terms of power consumption and life years. Hence Statement 3 is correct and 2 is Not Correct.

 Important Points

LED

  • LED is known as "Light Emitting Diode".
  • A light-emitting diode (LED) is a two-lead semiconductor light source.
  • It is a p–n junction diode, which emits light when activated.
  • When a suitable voltage is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons.
  • This effect is called electroluminescence, and the color of the light corresponds to the energy of the photon.

CFL

  • CFLs contain toxic mercury.
  • A fluorescent lamp is a low-pressure mercury-vapor gas-discharge lamp.
  • Electrons that are bound to mercury atoms are excited to states where they will radiate ultraviolet light as they return to a lower energy level.
  • This emitted ultraviolet light is converted into visible light as it strikes the fluorescent coating on the bulb (phosphor coating).

Related Questions

What is the difference between a CFL and an LED lamp? 1. To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semi-conductor material. 2. The average life span of a CFL is much longer than that of an LED lamp. 3. A CFL is less energy-efficient as compared to an LED lamp. Which of the statements given above is/are correct?
What is the difference between a CFL and an LED Lamp?
1. To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semi-conductor material.
2. The average life span of a CFL is much longer than of an LED lamp.
3. A CFL is less energy efficient as compared to an LED lamp.
Which of the statements given above is/are correct?
Consider the following statements: A. The average life span of a CFL is much longer than that of an LED lamp. B. A CFL is less energy efficient as compared to an LED lamp. Which of the above statements is/are correct? Select the code for the correct answer from the options given below:
Lamp A is less bright than Lamp B; Lamp B is less brighter than Lamp C; Lamp C is as bright as Lamp D. Lamp B is brighter than Lamp D and Lamp D is brighter than Lamp A. Which lamp is the brightest ?
Lamp A is less bright than Lamp B; Lamp B is Brighter than lamp C; Lamp C is as bright as Lamp D. Lamp B is brighter than Lamb D and Lamp D is better than Lamp A. Which is the brightest?
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.
The average of eight batsmen J, K, L, M, N, O, R, and T is compared. The number of batsman having average less than L are same as the number of batsman having average more than M. Average of T is less than M and more than K. Average of L is less than K. Average of two batsman lies between the average of M and L. Average of O is less than N and K both. Which of the following can be the correct sequence of their averages?
Assertion (A): Light Emitting Diode (LED) lamps offer longer service life as compared to Compact Fluorescent Lamps (CFL).
Reason (R): Light Emitting Diodes (LED) lamps are more energy efficient as compared to the Compact Fluorescent Lamps (CFL).
Select the correct answer:
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 life span 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.  
From the given table, what is the percentage of students scoring 40 or more, but less than 70. Scores Less than 20 Less than 30 Less than 40 Less than 50 Less than 60 Less than 70 Less than 80 No. of Students 12 19 22 31 38 46 50