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In interference and diffraction, the light energy is redistributed. If it reduces in one region, producing a dark fringe, it increases in another region, producing a bright fringe.
A. As there is no gain or loss of energy, these phenomena are consistent with the principle of conservation of energy.
B. Diffraction and interference are characteristics exhibited only by light waves.
Choose the correct answer from the options given below:

Asked in NEET 2026 · Intensity and coherent sources

• (1) A is false, but B is true
• (2) A is true and B is also true
• (3) A is true, but B is false
• (4) Both A and B are false

Step-by-step solution

Why the other options are wrong

• (1) Both parts are reversed: A is true, since the energy is only redistributed, and B is false, since every kind of wave interferes and diffracts.
• (2) B is false: sound waves, water waves and electron matter waves also interfere and diffract.
• (4) A is true: the dark fringes lose exactly the energy the bright fringes gain, so nothing is created or destroyed.

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