Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ρ (the lower case Greek letter rho), although the Latin letter D can also be used. Mathematically, density is defined as mass divided by volume: where ρ is the density, m is the mass, and V is the volume. In some cases (for instance, in the United States oil and gas industry), density is loosely defined as its weight per unit volume, although this is scientifically inaccurate – this quantity is more specifically called specific weight. For a pure substance the density has the same numerical value as its mass concentration.Different materials usually have different densities, and density may be relevant to buoyancy, purity and packaging. Osmium and iridium are the densest known elements at standard conditions for temperature and pressure. To simplify comparisons of density across different systems of units, it is sometimes replaced by the dimensionless quantity "relative density" or "specific gravity", i.e. the ratio of the density of the material to that of a standard material, usually water. Thus a relative density less than one relative to water means that the substance floats in water. The density of a material varies with temperature and pressure. This variation is typically small for solids and liquids but much greater for gases. Increasing the pressure on an object decreases the volume of the object and thus increases its density. Increasing the temperature of a substance (with a few exceptions) decreases its density by increasing its volume. In most materials, heating the bottom of a fluid results in convection of the heat from the bottom to the top, due to the decrease in the density of the heated fluid, which causes it to rise relative to denser unheated material. The reciprocal of the density of a substance is occasionally called its specific volume, a term sometimes used in thermodynamics. Density is an intensive property in that increasing the amount of a substance does not increase its density; rather it increases its mass. Other conceptually comparable quantities or ratios include specific density, relative density (specific gravity), and specific weight. (Wikipedia).
Physical Science 3.4b - Density
Density. The definition of density, the equation for density, and some numerical examples.
From playlist Physical Science Chapter 3 (Complete chapter)
Keep going! Check out the next lesson and practice what you’re learning: https://www.khanacademy.org/math/geometry/hs-geo-solids/hs-geo-density/e/surface-and-volume-density-word-problems Volume density is the amount of a quantity (often mass) per unit of volume. Density=Quantity/Volume
From playlist High School Geometry | High School Math | Khan Academy
What is Density? | Gravitation | Physics | Don't Memorise
Understanding the concept of Density is very important in order to understand Physics. Watch this video to fully grasp the idea of density. To get access to the entire course based on Gravitation, enroll here: https://infinitylearn.com/microcourses?utm_source=youtube&utm_medium=Soical&u
From playlist Physics
From playlist h. Three-Dimensional Measurement
Learn more about density! http://www.flippingphysics.com/density.html
From playlist Vertical Videos
Physics - E&M: Ch 40.1 Current & Resistance Understood (16 of 17) What is Current Density?
Visit http://ilectureonline.com for more math and science lectures! In this video I will explain the current density, for example, of a conductor of a given current (I) and current density (J) is defined as the amount of current per unit area. Next video in this series can be seen at: ht
From playlist THE "WHAT IS" PLAYLIST
Physics - E&M: Ch 40.1 Current & Resistance Understood (17 of 17) What is Current Density? Ex.
Visit http://ilectureonline.com for more math and science lectures! In this video I will find the current density, J=?, given current, I=4amps, and diameter, D=2mm. First video in this series can be seen at: https://youtu.be/bDe4lzgQY2E
From playlist THE "WHAT IS" PLAYLIST
What is Relative Density? | Physics | Don't Memorise
Now that you know what Density means, it would be quite easy for you to understand what Relative Density means. Watch this video to know more. ✅To learn more about Relative Density enroll in our full course now: https://infinitylearn.com/microcourses?utm_source=youtube&utm_medium=Soical&
From playlist Physics
In this video, the Flipping Physics team discusses the concept of mass and density by comparing the mass and density of steel and wood. The team first addresses the misconception that steel is always more massive than wood, explaining that the mass of an object cannot be determined without
From playlist Fluids
Lec 7 | MIT 3.320 Atomistic Computer Modeling of Materials
Technical Aspects of Density Functional Theory View the complete course at: http://ocw.mit.edu/3-320S05 License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
From playlist MIT 3.320 Atomistic Computer Modeling of Materials
Robert Seiringer: The local density approximation in density functional theory
We present a mathematically rigorous justification of the Local Density Approximation in density functional theory. We provide a quantitative estimate on the difference between the grand-canonical Levy-Lieb energy of a given density (the lowest possible energy of all quantum st
From playlist Mathematical Physics
Physics - Ch 22A Test Your Knowledge: Thermal Expansion (4 of 20) Fractional Change Above Surface
Visit http://ilectureonline.com for more math and science lectures! We will find what is the initial fraction of the block above the liquid. And how much will that fraction change for a small change in temperature. To donate: http://www.ilectureonline.com/donate https://www.patreon.com/u
From playlist PHYSICS 22A TEST YOUR KNOWLEDGE: THERMAL EXPANSION
Fluid Pressure, Density, Archimede & Pascal's Principle, Buoyant Force, Bernoulli's Equation Physics
This physics video tutorial provides a nice basic overview / introduction to fluid pressure, density, buoyancy, archimedes principle, pascal's principle and bernoulli's equation. This video contains plenty of notes, equations / formulas, examples, and practice problems for you to learn fr
From playlist New Physics Video Playlist
Hydrometer Physics Problems - Density & Specific Gravity Calculations
This video tutorial explains how to solve hydrometer problems in physics. It discusses how it works and explains how to calculate the density of the hydrometer and how to use it to calculate the density and specific gravity of the surrounding fluid. This video contains plenty of examples
From playlist New Physics Video Playlist
Worldwide Calculus: Mass and Density
Lecture on 'Mass and Density' from 'Worldwide Integral Calculus' and 'Worldwide AP Calculus'. For more lecture videos and $10 digital textbooks, visit www.centerofmath.org.
From playlist Applications of Integration
Lecture 11-Jack Simons Electronic Structure Theory- Density functional theory
Density functional theory fundamentals, strengths and weaknesses. (1)Jack Simons Electronic Structure Theory- Session 1- Born-Oppenheimer approximation http://www.youtube.com/watch?v=Z5cq7JpsG8I (2)Jack Simons Electronic Structure Theory- Session 2- Hartree-Fock http://www.youtube.co
From playlist U of Utah: Jack Simons' Electronic Structure Theory course
Physics - Mechanics: Fluid Statics: Buoyance Force (8 of 9) Floating in Multiple Layers: 2
Visit http://ilectureonline.com for more math and science lectures! In this video I will find the heights of the completely submerged object in the 2 different layers of liquid. Next video can be found at: https://youtu.be/EzNz5_lk6yM
From playlist PHYSICS 33.5 BUOYANCY FORCE
Density, Mass & Volume - Mixtures | Grade 6+ Series | GCSE Maths Tutor
A video revising the techniques and strategies for solving problems with density when materials are being mixed together This video is part of the Compound Measures module in GCSE maths, see my other videos below to continue with the series. Revision videos: The Entire GCSE in Only 2 Ho
From playlist GCSE Maths Videos
Teach Astronomy - Density Parameter
http://www.teachastronomy.com/ Another fundamental quantity of the big bang model is the density parameter. It's defined as the ratio of the mean density of the universe to the density just needed to overcome the cosmic expansion. The density parameter is denoted by the Greek symbol capi
From playlist 22. The Big Bang, Inflation, and General Cosmology