In amplitude modulation (AM), the relationship between frequency and pitch is indirect. Let's understand it in more detail:
Frequency refers to the number of cycles per second in a wave and is typically measured in Hertz (Hz). It determines the rate at which the waveform repeats itself.
Pitch, on the other hand, is a subjective perception of the frequency of a sound. It represents how high or low a sound is perceived by our ears.
In AM, the carrier wave's frequency is modulated (varied) in accordance with the amplitude of the modulating signal (often an audio signal). The modulating signal is usually an audio waveform that represents the original sound we want to transmit.
When the amplitude of the modulating signal is high, it causes variations in the amplitude of the carrier wave, resulting in the carrier wave's frequency being shifted above and below its original frequency. This process is known as frequency modulation.
Now, regarding pitch, the human ear perceives changes in frequency as changes in pitch. When the frequency of a sound wave increases, the pitch is perceived as higher, and when the frequency decreases, the pitch is perceived as lower.
In AM, since the frequency of the carrier wave is being modulated, the resulting modulated signal will contain frequency components that are both higher and lower than the carrier wave's original frequency. As a result, the perceived pitch of the modulated signal may change compared to the original audio signal. However, it's important to note that the pitch perception can be influenced by various factors, and the relationship between the modulated signal's frequency and perceived pitch can be complex.
In summary, in AM, modulation affects the frequency of the carrier wave, which can indirectly impact the perceived pitch of the modulated signal.