WOW.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Density - Wikipedia

    en.wikipedia.org/wiki/Density

    Density ( volumetric mass density or specific mass) is a 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: [1] where ρ is the density, m is the mass, and V is the volume ...

  3. Relative density - Wikipedia

    en.wikipedia.org/wiki/Relative_density

    Relative density, also called specific gravity, is a dimensionless quantity defined as the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water at its densest (at 4 °C or 39.2 °F); for gases, the reference is air ...

  4. Probability density function - Wikipedia

    en.wikipedia.org/wiki/Probability_density_function

    In probability theory, a probability density function ( PDF ), density function, or density of an absolutely continuous random variable, is a function whose value at any given sample (or point) in the sample space (the set of possible values taken by the random variable) can be interpreted as providing a relative likelihood that the value of ...

  5. Buoyancy - Wikipedia

    en.wikipedia.org/wiki/Buoyancy

    e. Buoyancy ( / ˈbɔɪənsi, ˈbuːjənsi / ), [1] [2] or upthrust, is a gravitational force, a net upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus, the pressure at the bottom of a column ...

  6. Population density - Wikipedia

    en.wikipedia.org/wiki/Population_density

    Population density is the number of people per unit of area, usually transcribed as "per square kilometer" or square mile, and which may include or exclude, for example, areas of water or glaciers. Commonly this is calculated for a county, city, country, another territory or the entire world . The world's population is around 8,000,000,000 [3 ...

  7. Hydrometer - Wikipedia

    en.wikipedia.org/wiki/Hydrometer

    The lower the density of the fluid, the deeper the weighted float B sinks. The depth is read off the scale A. A hydrometer or lactometer is an instrument used for measuring density or relative density of liquids based on the concept of buoyancy. They are typically calibrated and graduated with one or more scales such as specific gravity .

  8. Number density - Wikipedia

    en.wikipedia.org/wiki/Number_density

    The number density (symbol: n or ρN) is an intensive quantity used to describe the degree of concentration of countable objects ( particles, molecules, phonons, cells, galaxies, etc.) in physical space: three-dimensional volumetric number density, two-dimensional areal number density, or one-dimensional linear number density.

  9. Non-Newtonian fluid - Wikipedia

    en.wikipedia.org/wiki/Non-Newtonian_fluid

    t. e. A non-Newtonian fluid is a fluid that does not follow Newton's law of viscosity, that is, it has variable viscosity dependent on stress. In particular, the viscosity of non-Newtonian fluids can change when subjected to force. Ketchup, for example, becomes runnier when shaken and is thus a non-Newtonian fluid.