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2 years ago

7

When a piano tuner strikes both the A on the piano and a 440 Hz tuning fork, he hears a beat every 2 seconds. The frequency of t

he piano's A is

1 answer:

AysviL [449]2 years ago

3 0

Answer:

The frequency is $f = 439.5 \ Hz$

Explanation:

From the question we are told that

The frequency of the tuning fork is $f_t = 440 \ Hz$

The beat period is $T = 2 \ s$

Generally the beat frequency is mathematically represented as

$f_b = \frac{1}{T}$

$f_b = \frac{1}{2}$

$f_b = 0.5 \ Hz$

The beat frequency is also represented mathematically as

$f_b = f_t - f$

Where $f$ is the frequency of the piano

So

$f = 440 - 0.5$

$f = 439.5 \ Hz$

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2 years ago

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Explanation:

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The force acting on the charged particle in the magnetic field is given by :

$F=q(v\times B)$

$F=1.6\times 10^{-19}\times (5.92\times 10^7 i\times (-3257.1i+19911.5j+48381.8k)\times 10^{-9})$

Since, $i\times j=k\ \\j\times k=i\\k\times i=j$

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