⚡️🔝How do you explain density easily? "THE 3-4&5D = The Level of DENSITY not dimensions. Spectral Power Density: refers the distribution of power into frequency components composing that signal. According to Fourier analysis, any physical signal can be decomposed into a number of discrete frequencies, or a spectrum of frequencies over a continuous range. The statistical average of any sort of signal (including noise) as analyzed in terms of its frequency content, is called its spectrum.
When the energy of the signal is concentrated around a finite time interval, especially if its total energy is finite, one may compute the energy spectral density. More commonly used is the power spectral density (or simply power spectrum), which applies to signals existing over all time, or over a time period large enough (especially in relation to the duration of a measurement) that it could as well have been over an infinite time interval. The power spectral density (PSD) then refers to the spectral energy distribution that would be found per unit time, since the total energy of such a signal over all time would generally be infiniteThe simple answer is how heavy something is for its size. If something seems very heavy for its size (like a heavy metal object), we say it is more dense. If something seems light for its size (like a bag of cotton or pumice rock), then we say it has low density. Mass is the amount of matter in an object. 💎💎What is the highest density of light?

The medium having highest optical density is 💎 (Refractive Index 2.42) and the medium having lowest optical density is Air (Refractive Index 1.0003). LIGHT