There are different approaches to flight. If an object has a lower density than air, then it is buoyant and is able to float in the air without using energy. A heavier than air craft, known as an aerodyne, includes flighted animals and insects, fixed-wing aircraft and rotorcraft. Because the craft is heavier than air, it must generate lift to overcome its weight. The wind resistance caused by the craft moving through the air is called drag and is overcome by propulsive thrust except in the case of gliding.
Some vehicles also use thrust for flight, for example rockets and Harrier Jump Jets.
Finally, momentum dominates the flight of ballistic flying objects.
Read more about this topic: Flight
Other articles related to "physics":
... The idea that Newtonian physics proved causal determinism was highly influential in the early modern period ... For instance, Newtonian physics admits solutions where particles accelerate continuously, heading out towards infinity ...
... In a non-tonal language, segments may be differentiated as follows Vowels are replaced by a set of relative pitch ranges generally tracking the f2 formant of spoken language ... Stress is expressed by higher pitch or increased length Consonants are produced by pitch transitions of different lengths and height, plus the presence or absence of occlusion ...
... The Institute for Theoretical and Experimental Physics (ITEP Russian ... December 1, 1945, ITEP exists as a community of people studying topics ranging from theoretical physics and mathematics to biology and chemistry ... Research areas in theoretical physics concentrate around quantum field theory including the string theory ...
... Further information List of unsolved problems in physics Research in physics is continually progressing on a large number of fronts ... In condensed matter physics, an important unsolved theoretical problem is that of high-temperature superconductivity ... In particle physics, the first pieces of experimental evidence for physics beyond the Standard Model have begun to appear ...
... Information has a well-defined meaning in physics ... Bekenstein claimed that a growing trend in physics was to define the physical world as being made of information itself (and thus information is defined in this way) (see Digital physics) ...
Famous quotes containing the word physics:
“He who is conversant with the supernal powers will not worship these inferior deities of the wind, waves, tide, and sunshine. But we would not disparage the importance of such calculations as we have described. They are truths in physics because they are true in ethics.”
—Henry David Thoreau (18171862)
“... it is as true in morals as in physics that all force is imperishable; therefore the consequences of a human action never cease.”
—Tennessee Claflin (18461923)
“Now the twitching stops. Now you are still. We are through with physiology and theology, physics begins.”
—Alfred Döblin (18781957)