Final answer:
The higher pitch in an octave vibrates at a ratio of 2:1 compared to the lower pitch. This means the frequency of the higher pitch is twice as much as the lower pitch. For instance, if a lower 'A' note has a frequency of 440 Hz, an 'A' note an octave higher would have a frequency of 880 Hz.
Step-by-step explanation:
In music, the frequency of a pitch is the measure of its vibration per second, and this is measured in Hertz (Hz). In relation to the lower pitch in an octave, the higher pitch vibrates at a ratio of 2:1.
For example, if you play an 'A' note on a piano keyboard which vibrates at 440 Hz, the 'A' key an octave higher will vibrate at 880 Hz. This is doubled because an octave is the interval between one musical pitch and another with double its frequency. Therefore, the higher pitch is twice the frequency of the lower pitch.
Learn more about Pitch and Frequency