Definition of Amplitude
The amplitude of a periodic variable is a measure of its change in a single period (such as time or spatial period). The amplitude of a non-periodic signal is its magnitude compared with a reference value. There are various definitions of amplitude (see below), which are all functions of the magnitude of the differences between the variable's extreme values. In older texts, the phase of a periodic function is sometimes called the amplitude.
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Questions people ask
Real questions from the Stack Exchange community – follow a link to read the discussion.
- Would you hear a gravitational wave, if its amplitude and frequency were suitable? · Physics SE
- How do computers store sound waves just by sampling the amplitude of a wave and not the frequency? · Physics SE
- In what units is a sample's amplitude value represented, and how it relates to the real world? · Sound Design SE
- How to generate tones of different amplitude with Arduino · Electronics SE
- In a line-level audio signal, what function of voltage produces amplitude? · Electronics SE
- How does doubling the voltage amplitude change the decibels? · Electronics SE
Frequently asked questions
What is Amplitude?
The amplitude of a periodic variable is a measure of its change in a single period (such as time or spatial period). The amplitude of a non-periodic signal is its magnitude compared with a reference value.