Question

Musical notes are classified by frequency. The note middle C has a frequency of 262 hertz. The note C above middle C has a frequency of 524 hertz. The note C below middle C has a frequency of 131 hertz.

1) Write an equation of the sine function that represents middle C if its amplitude is 0.2.

2)Write an equation of the sine function that represents C above middle C if its amplitude is one half that of middle C.

3)Write an equation of the sine function that represents C below middle C if its amplitude is twice that of middle C.

Answer 1

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Answer:

1) f(t) = 0.2·sin(524π·t)

2) f(t) = 0.1·sin(1048π·t)

3) f(t) = 0.4·sin(262π·t)

Explanation:

The general form of the desired equation is ...

f(t) = A·sin(2πf·t)

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1) f = 262; A = 0.2

f(t) = 0.2·sin(524π·t)

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2) f = 524; A = 0.1

f(t) = 0.1·sin(1048π·t)

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3) f = 131; A = 0.4

f(t) = 0.4·sin(262π·t)