rotational drag
21Turbocharger — A turbocharger, or turbo, is an air compressor used for forced induction of an internal combustion engine. Like a supercharger, the purpose of a turbocharger is to increase the mass of air entering the engine to create more power. However, a… …
22Dynamometer — For the dynamometer used in railroading, see dynamometer car .A dynamometer or dyno for short, is a machine used to measure torque and rotational speed (rpm) from which power produced by an engine, motor or other rotating can be calculated.A… …
23Vortex — A vortex (pl. vortices ) is a spinning, often turbulent, flow of fluid. Any spiral motion with closed streamlines is vortex flow. The motion of the fluid swirling rapidly around a center is called a vortex. The speed and rate of rotation of the… …
24Flight dynamics — is the science of air and space vehicle orientation and control in three dimensions. The three critical flight dynamics parameters are the angles of rotation in three dimensions about the vehicle s center of mass, known as pitch , roll and yaw… …
25Propfan — NASA / GE Unducted Fan A propfan was first defined as a small diameter, highly loaded multiple bladed variable pitch propulsor having swept blades with thin advanced airfoil sections, integrated with a nacelle contoured to retard the airflow… …
26Hard disk drive — Hard drive redirects here. For other uses, see Hard drive (disambiguation). Hard disk drive Mechanical interior of a modern hard disk drive Date invented 24 December 1954 [1] …
27Axial compressor — Axial compressors are rotating, aerofoil based compressors in which the working fluid principally flows parallel to the axis of rotation. This is in contrast with centrifugal, axi centrifugal and mixed flow compressors where the air may enter… …
28Field hockey stick — In Field hockey, each player carries a stick and cannot take part in the game without it. The stick is usually between 36 and 38 long (but this is not defined or restricted)and traditionally made of wood but now almost all the more expensive… …
29Bicycle helmet — A bicycle helmet is a helmet intended to be worn while riding a bicycle. They are designed to attenuate impacts to the skull of a cyclist in falls while minimizing side effects such as interference with peripheral vision.[1] There is an active… …
30Stellar rotation — is the angular motion of a star about its axis. The rate of rotation can be measured from the spectrum of the star, or by timing the movements of active features on the surface.The rotation of a star produces an equatorial bulge due to… …
