Can people can tell exactly in which octave a note is played?

The octave relationship is a natural phenomenon that has been referred to as the "basic miracle of music," the use of which is "common in most musical systems." The interval between the first and second harmonics of the harmonic series is an octave.
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Octave.

1. How do you know what octave a note is in?
2. Do two notes of an octave sound exactly the same?
3. How do you explain octaves?
4. Why do humans hear octaves?

How do you know what octave a note is in?

Each of the staff lines, and the spaces in between them, represent a note relative to Middle C. Another convention, often used with computer music, is to follow the note with an octave number. For example, Middle C might be labelled C4, while C5 would be the C note one octave up from it.

Do two notes of an octave sound exactly the same?

The two notes of an octave sound exactly the same due to the simple relationship of their frequencies. When calculating intervals, both the start and end notes should be included in the count.

How do you explain octaves?

In terms of music, an octave is the distance between one note (like C#) and the next note bearing its same name (the next C# that's either higher or lower). In terms of physics, an octave is the distance between one note and another note that's double its frequency.

Why do humans hear octaves?

In essence, pitch is the brain's way of grouping harmonically related sounds. ... Pitch perception allows us to focus on a conversation in a noisy environment, for example. The same notes in different octaves are harmonically related: a harmonic series based on a low “C” note contains the frequencies of every higher C.