JEE Main 2014PhysicsElectromagnetic WavesEasyMCQ

JEE Main 2014 — Electromagnetic Waves Question with Solution

JEE Main 2014 (09 Apr Online)

Question

Match List I (Wavelength range of electromagnetic spectrum) with List II (Method of production of these waves) and select the correct option from the options given below the lists.
  List I   List II
(a) 700 nm to 1 mm (i) Vibration of atoms and molecules.
(b) 1 nm to 400 nm (ii) Inner shell electrons in atoms moving from one energy level to a lower level.
(c) < 10-3 nm (iii) Radioactive decay of the nucleus.
(d) 1 mm to 0.1 m (iv) Magnetron valve.

Choose an option

Show full solutionCorrect option: B
Correct answer
B(a) - (i), (b) - (ii), (c) - (iii), (d) - (iv)

Step-by-step explanation

We know, the range of wavelengths between 700 nm to 1 mm, is referred as Infrared rays. These are produced by heating an object to such an extent that the molecules start vibrating and it radiates infrared waves. When the object is not hot enough such that it can emit visible light, therefore, it radiates Infrared waves.
Thus, option (a) in list I matches with Option (i) in list II.


The range of wavelengths between 1 nm to 400 nm, is referred to as ultraviolet rays. Ultraviolet rays are produced due to atomic excitation in a gaseous discharge tube. This atomic excitation occurs when an atom from one energy level jumps to a lower energy level.
Thus, option (b) in list I matches with Option (ii) in list II.

The range of wavelengths <10-3 nm are known as the Gamma rays. Some of the radioactive substances, when decay releases a spectrum, which falls in the range of <10-3 nm, they emit electromagnetic waves called the gamma rays.
Thus, we can say, Thus, option (c) in list I matches with Option (iii) in list II.

We know again, the range of wavelength 1 mm to 0.1 m, is referred to as microwaves, and they are produced inside an oven in a tube like structure, called the magnetron.

Thus, we can say, option (d) in list I matches with Option (iv) in list II.

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About this question

This is a previous-year question from JEE Main 2014, covering the Electromagnetic Waves chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.