Two tuning forks with similar frequencies; one fork is variable in frequency to tune beating.
What it shows:
The interference of waves from two tuning forks of slightly differing frequencies gives rise to beating, that is, a modulated wave of frequency.
νb = (ν1 - ν2)
How it works:
Using two tuning forks of 256Hz, with one of the pair having small clamps (see figure 1) attached to the fork's limbs. These alter the fork's resonant frequency, and adjustment of the clamp...
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