the space shuttle is a partially reusable low earth orbital spacecraft system that was operated from 1981 to 2011 by the u.s. national aeronautics and space administration nasa as part of the space shuttle program.its official program name was space transportation system sts , taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development.
sulfur is a component of gunpowder 'black powder' . fertilizer. sulfur is increasingly used as a component of fertilizers. the most important form of sulfur for fertilizer is the mineral calcium sulfate. elemental sulfur is hydrophobic not soluble in water and cannot be used directly by plants. over time, soil bacteria can convert it to .
in fluid dynamics, a vortex plural vortices/vortexes is a region in a fluid in which the flow revolves around an axis line, which may be strht or curved. vortices form in stirred fluids, and may be observed in smoke rings, whirlpools in the wake of a boat, and the winds surrounding a tropical cyclone, tornado or dust devil.. vortices are a major component of turbulent flow.
random-access memory ram / r æ m / is a form of computer memory that can be read and changed in any order, typically used to store working data and machine code. a random-access memory device allows data items to be read or written in almost the same amount of time irrespective of the physical location of data inside the memory. in contrast, with other direct-access data storage media such .
cross-stitch is a form of sewing and a popular form of counted-thread embroidery in which x-shaped stitches in a tiled, raster-like pattern are used to form a picture. the stitcher counts the threads on a piece of evenweave fabric such as linen in each direction so that the stitches are of uniform size and appearance.this form of cross-stitch is also called counted cross-stitch in order to .
in natural gas and oil pipelines, binder materials such as paraffins, glycols, and asphaltenes marry up with fine ferrous and sand particles trapping to the magnetic fields when passing through the black powder separators. the black powder contamination trapped on the magnetic separators is easily removed and stored in mineral bags. when the .
psychological resilience is the ability to mentally or emotionally cope with a crisis or to return to pre-crisis status quickly. resilience exists when the person uses 'mental processes and behaviors in promoting personal assets and protecting self from the potential negative effects of stressors'.
the strategic defense initiative sdi was a proposed missile defense system intended to protect the united states from attack by ballistic strategic nuclear weapons intercontinental ballistic missiles and submarine-launched ballistic missiles .the concept was first announced publicly by president ronald reagan on 23 march 1983. reagan was a vocal critic of the doctrine of mutual assured .
the index of physics articles is split into multiple pages due to its size.. to navigate by individual letter use the table of contents below.
carbon is the fourth most abundant chemical element in the observable universe by mass after hydrogen, helium, and oxygen. carbon is abundant in the sun, stars, comets, and in the atmospheres of most planets. some meteorites contain microscopic diamonds that were formed when the solar system was still a protoplanetary disk.
magnetic resonance imaging mri is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. mri scanners use strong magnetic fields, magnetic field gradients, and radio waves to generate images of the organs in the body. mri does not involve x-rays or the use of ionizing radiation, which distinguishes it from ct and pet scans.