A string $2.0 \mathrm{~m}$ long and fixed at its ends is driven by a 240 Hz vibrator. The string vibrates in its third harmonic mode. The speed of the wave and its fundamental frequency is:

Question:

A string $2.0 \mathrm{~m}$ long and fixed at its ends is driven by a 240 Hz vibrator. The string vibrates in its third harmonic mode. The speed of the wave and its fundamental frequency is:

  1. $180 \mathrm{~m} / \mathrm{s}, 80 \mathrm{~Hz}$

  2. $320 \mathrm{~m} / \mathrm{s}, 80 \mathrm{~Hz}$

  3. $320 \mathrm{~m} / \mathrm{s}, 120 \mathrm{~Hz}$

  4. $180 \mathrm{~m} / \mathrm{s}, 120 \mathrm{~Hz}$

JEE Main Previous Year Single Correct Question of JEE Main from Physics Waves chapter.

JEE Main Previous Year 9 April 2019 (II)


Correct Option: 2

Solution:

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