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A rocket's required mass ratio as a function of effective exhaust velocity ratio. The classical rocket equation, or ideal rocket equation is a mathematical equation that describes the motion of vehicles that follow the basic principle of a rocket: a device that can apply acceleration to itself using thrust by expelling part of its mass with high velocity and can thereby move due to the ...
An ejection fraction (EF) is the volumetric fraction (or portion of the total) of fluid (usually blood) ejected from a chamber (usually the heart) with each contraction (or heartbeat). It can refer to the cardiac atrium , [ 1 ] ventricle , [ 2 ] gall bladder, [ 3 ] or leg veins, [ 4 ] although if unspecified it usually refers to the left ...
Myocardial infarction or cardiomyopathy causes damage to the myocardium, which impairs the heart's ability to eject blood and, therefore, reduces ejection fraction. This reduction in the ejection fraction can manifest itself as heart failure. Low EF usually indicates systolic dysfunction, and severe heart failure can result in EF lower than 0.2 ...
Specific impulse in turn has deep impacts on the achievable delta-v and associated orbits achievable, and (by the rocket equation) mass fraction required to achieve a given delta-v. Optimizing the tradeoffs between mass fraction and specific impulse is one of the fundamental engineering challenges in rocketry.
The formula for the velocity of a body in a circular orbit at distance r from the center of gravity of mass M can be derived as follows: Centrifugal acceleration matches the acceleration due to gravity.
Flux F through a surface, dS is the differential vector area element, n is the unit normal to the surface. Left: No flux passes in the surface, the maximum amount flows normal to the surface.
SVs are also used to calculate ejection fraction, which is the portion of the blood that is pumped or ejected from the heart with each contraction. To calculate ejection fraction, SV is divided by EDV. Despite the name, the ejection fraction is normally expressed as a percentage.
Classical mechanics is the branch of physics used to describe the motion of macroscopic objects. [1] It is the most familiar of the theories of physics. The concepts it covers, such as mass, acceleration, and force, are commonly used and known. [2]