Physical quantity
A physical quantity (or "physical magnitude") is a physical property of a phenomenon, body, or substance, that can be quantified by measurement.
An extensive quantity is equal to the sum of that q...
The Last Artifact
This is "The Last Artifact" by The Last Artifact on Vimeo, the home for high quality videos and the people who love them.
The Debate Over Time's Place in the Universe
Physicists can’t agree on whether the flow of future to past is real or a mental construct.
'Mistakes' (New Zealand road safety advert)
The powerful advert entitled 'Mistakes' attempts to make drivers think twice about speeding. Two drivers are seen on a path to collision when time slows down and stops, allowing them to get out of th...
Five Little Things You Can Do to Make Your Home More Energy Efficient
An informative article about improving the energy efficiency of a house.
A Nanophotonic Comeback For Incandescent Bulbs?
Researchers combine the warm look of traditional light bulbs with 21st-century energy efficiency. Incandescent lighting and its warm, familiar glow is well over a century old yet survives virtually un...
When Time Breaks Down | Space Time | PBS Digital Studios
This episode on the physics of time syncs perfectly with Pink Floyd's 'Dark Side of the Moon.'
How Axions May Explain Time’s Arrow
The irreversibility of time may be a clue as to what makes up the universe’s dark matter.
How Funny Is This Word? The 'Snunkoople' Effect
How do you quantify something as complex and personal as humour? University of Alberta researchers have developed a mathematical method of doing just that—and it might not be quite as personal as we t...
Plant lamps powered by soil nutrients bring electricity to remote areas of Peru
In parts of the world that don’t have steady access to the electricity grid, finding power for essential things like night lighting are an ongoing challenge. While you can burn kerosene in lamps to pr...
The Dirty Secret Behind Electric Cars
As the world tries to reduce greenhouse-gas emissions and combat climate change, policymakers have pinned hopes on electric cars, whose range and convenience are quickly improving. Alongside the boom ...
Germany is turning on its monster stellarator
For more than 60 years, scientists have dreamed of a clean, inexhaustible energy source in the form of nuclear fusion. And they're still dreaming. But thanks to the efforts of the Max Planck Institu...
Ballistic Pendulums Are As Awesome As They Sound
How does a ballistic pendulum give information about a bullet or ball? Here is a derivation of the classic introductory physics problem. ALTHOUGH IT’S NOT always so simple to set up, a ballistic pendu...
Quantum Experiment Shows How “Time” Doesn’t Exist As We Think It Does (Mind-Altering)
“We choose to examine a phenomenon which is impossible, absolutely impossible, to explain in any classical way, and which has in it the heart of quantum mechanics. In reality, it contains the only mys...
Magnetic Wormhole Created In Lab
Ripped from the pages of a sci-fi novel, physicists have crafted a wormhole that tunnels a magnetic field through space. "This device can transmit the magnetic field from one point in space to another...
Here's Why Years Seem To Go By Faster As You Get Older
Have you ever wondered, why does time fly? We’ve all noticed how summer vacations in our childhoods seemed to last an eternity — in fact, the days crawled by so slowly that most kids were almost excit...
The World’s Most Powerful Laser Has Just Been Fired In Japan
Scientists in Japan have set the record for the most powerful laser ever fired, producing a 2 petawatt pulse - that’s 2 quadrillion watts - using a device known as the Laser for Fast Ignition Experime...
Dimensional analysis
In engineering and science, dimensional analysis is the analysis of the relationships between different physical quantities by identifying their fundamental dimensions (such as length, mass, time, and...
SI base unit
The International System of Units (SI) defines seven units of measure as a basic set from which all other SI units are derived. The SI base units and their physical quantities are:The SI base quantiti...
SI derived unit
The International System of Units (SI) specifies a set of seven base units from which all other SI units of measurement are derived. Each of these other units (SI derived units) is either dimensionles...
Acceleration
Acceleration, in physics, is the rate of change of velocity of an object. An object's acceleration is the net result of any and all forces acting on the object, as described by Newton's Second Law. Th...
Acceleration - Wikipedia
Amount of substance
Amount of substance is a standards-defined quantity that measures the size of an ensemble of elementary entities, such as atoms, molecules, electrons, and other particles. It is sometimes referred to ...
Area
Area is the quantity that expresses the extent of a two-dimensional figure or shape, or planar lamina, in the plane. Surface area is its analog on the two-dimensional surface of a three-dimensional o...
Area - Wikipedia
Physical constant
A physical constant is a physical quantity that is generally believed to be both universal in nature and constant in time. It can be contrasted with a mathematical constant, which is a fixed numerical...
Density
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The symbol most often used for density is ρ (the lower case Greek letter rho). Mathematically, ...
Density - Wikipedia
Energy
In physics, energy is a property of objects, transferable among them via fundamental interactions, which can be converted into different forms but not created or destroyed. The joule is the SI unit of...
Energy - Wikipedia
Enthalpy
Enthalpy is a defined thermodynamic potential, designated by the letter "H", that consists of the internal energy of the system (U) plus the product of pressure (p) and volume (V) of the system:Since ...
Enthalpy - Wikipedia
Entropy
In thermodynamics, entropy (usual symbol S) is a measure of the number of specific ways in which a thermodynamic system may be arranged, commonly understood as a measure of disorder. According to the ...
Entropy - Wikipedia
Entropy (disambiguation)
Entropy is a measure of disorder in a system.
Length
In geometric measurements, length is the longest dimension of an object. In the International System of Quantities, length is any quantity with dimension distance. In other contexts "length" is the m...