power-to-space ratio
51Black body — As the temperature decreases, the peak of the blackbody radiation curve moves to lower intensities and longer wavelengths. The blackbody radiation graph is also compared with the classical model of Rayleigh and Jeans …
52Stirling engine — Alpha type Stirling engine. There are two cylinders. The expansion cylinder (red) is maintained at a high temperature while the compression cylinder (blue) is cooled. The passage between the two cylinders contains the regenerator …
53Multijunction photovoltaic cell — Multi junction solar cells or tandem cells are solar cells containing several p n junctions. Each junction is tuned to a different wavelength of light, reducing one of the largest inherent sources of losses, and thereby increasing efficiency.… …
54Mass driver — For fictional mass drivers, see List of electromagnetic projectile devices in fiction. Artist s conception of a mass driver for lunar launch A mass driver or electromagnetic catapult is a proposed method of non rocket spacelaunch which would use… …
55Automobile layout — In automotive design layout specifies where on the car the engine and drive wheels are found. Front wheel drive types A Front engine, front wheel drive layout places both the engine and driven wheels at the front of the vehicle. This layout is… …
56technology, history of — Introduction the development over time of systematic techniques for making and doing things. The term technology, a combination of the Greek technē, “art, craft,” with logos, “word, speech,” meant in Greece a discourse on the arts, both… …
57Fuel cell — For other uses, see Fuel cell (disambiguation). Demonstration model of a direct methanol fuel cell. The actual fuel cell stack is the layered cube shape in the center of the image A fuel cell is a device that converts the chemical energy from a… …
58Steam engine — A steam engine is a heat engine that performs mechanical work using steam as its working fluid. [ [http://www.britannica.com/EBchecked/topic/564472/steam engine steam engine Britannica Online Encyclopedia ] ] Steam engines have a long history,… …
59Gas turbine — Microturbine redirects here. For turbines in electricity, see Small wind turbine. For turbines driven by the flow of gas, see Turbine. A typical axial flow gas turbine turbojet, the J85, sectioned for display. Flow is left to right, multistage… …
60Wright R-975 — R 975 Whirlwind A Continental built R 975 from a Sherman tank Type Air cooled 9 cylind …
