For a string fixed at both the ends,
f=2Lnv
For third harmonic, 240=2(2)3v
⇒v=3240×4
=320ms−1
Fundamental frequency f0=2L1v
=41×320=80Hz
A string 2.0m long and fixed at its ends is driven by a 240Hz vibrator. The string vibrates in its third harmonic mode. The speed of the wave and its fundamental frequency is
Held on 9 Apr 2019 · Verified 6 Jul 2026.
320ms−1,120Hz
320ms−1,80Hz
180ms−1,80Hz
180ms−1,120Hz
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