Engineering

Turbine cooling turns night into day

Keeping turbines running efficiently during a hot Australian summer's day can be hard work. But a new technology is drawing on the cold night air to make it easier.

Energy & Green Tech

Chill out: Advanced solar tech runs cooler and lasts longer

Australian photovoltaics researchers have made a 'cool' discovery: Singlet fission and tandem solar cells—two innovative ways to generate solar power more efficiently—also help to lower operating temperatures and keep ...

Electronics & Semiconductors

Exploring extremes: When is it too hot to handle?

Exploring extreme environments can put significant operational challenges on the engineering systems we depend upon to safely explore and at times operate within.

Energy & Green Tech

Developing the world's 'hottest' heat pump

The heat pumps we use to heat our homes and domestic water operate at temperatures of between 30 and 60 degrees, but many industrial processes require much higher temperatures—and some industries require an entirely different ...

Engineering

Sunlight to solve the world's clean water crisis

Researchers at UniSA have developed a cost-effective technique that could deliver safe drinking water to millions of vulnerable people using cheap, sustainable materials and sunlight.

Energy & Green Tech

To cool tomorrow's buildings, power sector must grow

Temperatures are rising. Eight of the warmest 10 recorded years of globally averaged temperature have occurred after 1998. Coupled with that increase is a growing demand for electricity to cool buildings. A new study published ...

page 1 from 12

Temperature

In physics, temperature is a physical property of a system that underlies the common notions of hot and cold; something that feels hotter generally has the higher temperature. Temperature is one of the principal parameters of thermodynamics. If no heat flow occurs between two objects, the objects have the same temperature; otherwise heat flows from the hotter object to the colder object. This is the content of the zeroth law of thermodynamics. On the microscopic scale, temperature can be defined as the average energy in each degree of freedom in the particles in a system. Because temperature is a statistical property, a system must contain a few particles for the question as to its temperature to make any sense. For a solid, this energy is found in the vibrations of its atoms about their equilibrium positions. In an ideal monatomic gas, energy is found in the translational motions of the particles; with molecular gases, vibrational and rotational motions also provide thermodynamic degrees of freedom.

Temperature is measured with thermometers that may be calibrated to a variety of temperature scales. In most of the world (except for Belize, Myanmar, Liberia and the United States), the Celsius scale is used for most temperature measuring purposes. The entire scientific world (these countries included) measures temperature using the Celsius scale and thermodynamic temperature using the Kelvin scale, which is just the Celsius scale shifted downwards so that 0 K= −273.15 °C, or absolute zero. Many engineering fields in the U.S., notably high-tech and US federal specifications (civil and military), also use the kelvin and degrees Celsius scales. Other engineering fields in the U.S. also rely upon the Rankine scale (a shifted Fahrenheit scale) when working in thermodynamic-related disciplines such as combustion.

This text uses material from Wikipedia, licensed under CC BY-SA