Which among the following is true for propagation of sound waves ?

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Q: 89 (NDA-II/2021)
Which among the following is true for propagation of sound waves ?

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,24,58,12,47,6,17

keywords: 

{'transverse wave': [0, 0, 0, 1], 'sound waves': [0, 0, 2, 9], 'longitudinal wave': [0, 0, 0, 2], 'propagation': [2, 0, 0, 5], 'sound': [4, 3, 10, 15]}

Option 1 is incorrect. Sound cannot travel in a vacuum. This is because sound waves require a medium, such as air, water, or solid objects, to propagate. In a vacuum, there is no medium for the sound waves to travel through, so they cannot propagate.

Option 2 is the correct answer. Sound cannot travel in a vacuum, as mentioned above. However, in air, sound is a longitudinal wave. A longitudinal wave is a wave in which the particles of the medium vibrate in the same direction as the wave is propagating. In the case of sound in air, the air particles vibrate back and forth in the same direction as the sound wave is moving.

Option 3 is incorrect. While sound cannot travel in a vacuum, in air it is a longitudinal wave, not a transverse wave.

Option 4 is also incorrect. Sound cannot travel in a vacuum, and in air, it is a longitudinal wave, not a transverse wave.

In summary, sound cannot travel in a vacuum, and in air, it is a longitudinal wave.