Yes, the relative amplitude of an electromagnetic wave can correlate with the relative intensity of light falling on an object or surface and the relative brightness of the color perceived by an observer.
The intensity of light is related to the square of the amplitude of the electromagnetic wave. In other words, as the amplitude of the wave increases, the intensity of light also increases. So, if two electromagnetic waves have different amplitudes, the wave with the larger amplitude will generally have a higher intensity of light associated with it.
When light falls on an object or surface, it can be absorbed, transmitted, or reflected. The intensity of light falling on an object affects how much of it is absorbed or reflected. If the intensity of light is higher, more light will be absorbed or reflected, leading to a higher perceived brightness.
The perceived brightness of a color is influenced by both the intensity of light falling on the object and the sensitivity of the human visual system to different wavelengths of light. Brightness is subjective and can vary based on the individual's perception. However, in general, higher-intensity light tends to be perceived as brighter.
It's important to note that there are other factors that can affect the perceived brightness of an object or color, such as the background illumination, contrast, and the properties of the object itself (e.g., reflectivity, texture). Additionally, the color perception can be influenced by factors like color contrast and adaptation of the visual system.
Overall, while the relative amplitude of an electromagnetic wave can correlate with the relative intensity of light and the perceived brightness of a color, it's important to consider the various factors that can influence visual perception and the overall context of the situation.