Factbites
 Where results make sense
About us   |   Why use us?   |   Reviews   |   PR   |   Contact us  

Topic: Drag (physics)


  
  Drag
In physics, drag consists of the sum of all the aerodynamic forces[?] in the direction of the external airflow.
The overall drag of an object is characterized by a dimensionless number called the drag coefficient, and is calculated using the drag equation.
Drag is also slang for any costume, referring in particular to the ostentatiously glamorous costumes of the type worn by drag queens and kings.
www.ebroadcast.com.au /lookup/encyclopedia/dr/Drag.html   (254 words)

  
 Drag (physics) - Wikipedia, the free encyclopedia
In fluid dynamics, drag is the force that resists the movement of a solid object through a fluid (a liquid or gas).
For a solid object moving through a fluid or gas, the drag is the sum of all the aerodynamic or hydrodynamic forces in the direction of the external fluid flow.
is the drag coefficient (a dimensionless constant, e.g.
en.wikipedia.org /wiki/Drag_(physics)   (1206 words)

  
 What is Drag?
Drag is the aerodynamic force that opposes an aircraft's motion through the air.
Drag is generated by the difference in velocity between the solid object and the fluid.
Drag is a force and is therefore a vector quantity having both a magnitude and a direction.
www.grc.nasa.gov /WWW/K-12/airplane/drag1.html   (775 words)

  
 Basic Flight Physics
Drag is a force exerted on an object moving through a fluid; it is always oriented in the direction of relative fluid flow (try running against a high wind and you'll feel drag pushing you back in the direction of relative fluid flow).
Drag occurs because the fluid and the object exchange momentum when impacting, creating a force opposing the motion of the object.
Drag is very helpful, however, when a flying animal is trying to slow down or land; so in that case, animals spread out their wings (turning on the air brakes, so to speak).
www.ucmp.berkeley.edu /vertebrates/flight/physics.html   (1040 words)

  
 Drag
Drag is a resistance force generated by a solid object moving through a fluid.
Because skin friction drag is an interaction between a solid (the airplane surface) and a gas (the air), the magnitude of skin friction drag depends on the properties of both the solid and the gas.
Generally, interference drag will add to the component drags but in a few cases, for example, adding tip tanks to a wing, total drag will be less than the sum of the two component drags because of the reduction of induced drag.
www.centennialofflight.gov /essay/Theories_of_Flight/drag/TH4.htm   (1272 words)

  
 Air resistance   (Site not responding. Last check: 2007-10-16)
drag (or air resistance): the frictional force from the air that resists the forward motion of the object.
The drag force produced by the motion through water is the most important force in swimming as well and can be understood using the same ideas and formulas [that is why we use the word "fluid" below, which can be a gas or a liquid].
This is what happens in the drag force: the pressure in front of a moving object is somewhat greater than the pressure behind the object and the difference produces a net force that opposes the motion of the object through the air.
carini.physics.indiana.edu /E105/drag-force.html   (1526 words)

  
 The Drag Coefficient
The drag coefficient is a number that aerodynamicists use to model all of the complex dependencies of shape, inclination, and flow conditions on aircraft drag.
This equation is simply a rearrangement of the drag equation where we solve for the drag coefficient in terms of the other variables.
As pointed out on the drag equation slide, the choice of reference area (wing area, frontal area, surface area,...) will affect the actual numerical value of the drag coefficient that is calculated.
www.grc.nasa.gov /WWW/K-12/airplane/dragco.html   (869 words)

  
 Aerodynamic Drag
Drag is a complicated phenomena and explaining it from a theory based entirely on fundamental principles is exceptionally difficult.
Drag increases with the density of the fluid (ρ;).
Given the usual posture of a skydiver, his or her position, the type of clothes he or she wears, and the state of the air on the way down; your typical skydiver will not be able to exceed 55 to 60 m/s (200 to 210 km/h or 125 to 135 mph).
hypertextbook.com /physics/matter/drag   (1843 words)

  
 Drag   (Site not responding. Last check: 2007-10-16)
In physics, drag is a combination of aerodynamic or hydrodynamic forces.
In computing, to drag is to click the mouse button and hold it down while moving the mouse.
Drag is slang for any costume, but particularly for clothes of one gender worn by the opposite gender.
drag.iqnaut.net   (132 words)

  
 Drag of Blunt Bodies and Streamlined Bodies
This drag is associated with the formation of a wake, which can be readily seen behind a passing boat, and it is usually less sensitive to Reynolds number than the frictional drag.
Formally, both types of drag are due to viscosity (if the body was moving through an an inviscid fluid there would be no drag at all), but the distinction is useful because the two types of drag are due to different flow phenomena.
Frictional drag is important for attached flows (that is, there is no separation), and it is related to the surface area exposed to the flow.
www.princeton.edu /~asmits/Bicycle_web/blunt.html   (1069 words)

  
 Emory Physics | Colloquium Dec. 5, 2003
The motion of a solid object being pulled slowly through a granular medium is resisted by jamming of the grains, resulting in a drag force which differs dramatically from viscous drag in a fluid both in its average properties and in having large fluctuations.
We have studied the drag force and its fluctuations as a function of the velocity, the depth in the medium, the geometry of the dragged object, and the grain size and morphology.
The drag process provides an excellent test-bed for the strength of locally jammed states among the grains and the effects of confinement on the jamming.
www.physics.emory.edu /colloquia-archive/schiffer.html   (221 words)

  
 Olympians look to physics (August 2004) - Physics World - PhysicsWeb
Although surface friction drag is a relatively small part of the overall drag experienced by the swimmer, it is large enough to add several hundredths of a second to a competitor's time and could therefore make a crucial difference in the race for medals.
The outfit is made of rough material around areas where the drag is greatest, such as the chest and buttocks, but makes use of a smoother fabric in regions where the water flows more slowly, such as the inner legs.
For example, two cyclists with the same physical power, identical physique and matching technique travelling at 65 kph could be separated by just a couple of hundredths of a second at the finish line - equivalent to the difference of half a wheel - if the aerodynamic properties of their bikes are different.
www.physicsweb.org /article/world/17/8/3   (1106 words)

  
 Physics
The drag force acts in the opposite direction to the path of the ball.
When the airflow is laminar and the drag coefficient is high, the boundary layer of air on the surface of the ball "separates" relatively early as it flows over the ball, producing vortices in its wake.
One of the most critical problems is the difficulty of measuring the physical motion of humans, partly because their movements are so unpredictable.
www.soccerballworld.com /Physics.htm   (2426 words)

  
 The Physics of Racing
The focus of their efforts is on the aerodynamic forces of negative lift or downforce and drag.
Drag reduction is more critical on the speedway than on other circuits.
Since the drag force is proportional to the square of the speed, minimizing drag is a primary concern in the speedway setup.
www.nas.nasa.gov /About/Education/Racecar/physics.html   (596 words)

  
 The Physics in NASCAR
Without the application of physics in NASCAR, the cars would not be able to accomplish the feats that they are now capable of; straightaway speeds of nearly 200 mph and cornering speeds around 160 mph.
The major factor in speed was identified as the reduction of aerodynamic drag, but the problem was that air is invisible and so they didn’t know how to deal with it.
By reducing the aerodynamic drag, speeds increased, but as a result the cars lost a lot of handling and stability in the corners (Boone).
www.hesston.edu /academic/faculty/nelsonk/PhysicsResearch/Nascar/paper.htm   (1528 words)

  
 Drag force exercises   (Site not responding. Last check: 2007-10-16)
Assume a drag coefficient of 1.0 for the parachute.
To swim fast, the swimmer must overcome a strong drag force of the water on the body by exerting their own drag force of their hand back on the water.
Assume a drag coefficient of 0.30, an initial speed of 45 m/s, ball diameter of 0.074 m, mass of 0.149 kg.
carini.physics.indiana.edu /E105/ex-drag-force.html   (242 words)

  
 Aerodynamic Drag Machine: Drag Power Calculator
Although most wind turbines and windmills - new and old - are based on the lift principle rather than drag, it is worthwhile to explore the physics of drag-based wind machines.
The drag coefficients used for the hollow sphere, 1.42 and the flat plate, 1.1 are from White (1999) - see the bibliography.
The drag coefficients are not independent of the size of the object, as mentioned on the previous page about the Reynolds Number.
www.windpower.org /en/tour/wtrb/dragrace.htm   (1191 words)

  
 Vertical fall with quadratic air drag.
in which A and B are constants of integration, g is the acceleration of gravity, k=cm, where c is the drag constant and m is the mass of the bullet.
The force from the drag is in the same direction as the gravitational force on the way up.
Gravity acts downward, drag acts upward, the direction of the net force m dv/dt is given by the sign of dv/dt.
www.physicsforums.com /showthread.php?threadid=128252   (586 words)

  
 The Daily University Star | NEWS   (Site not responding. Last check: 2007-10-16)
The presentation incorporated pictures and film clips, including a crowd-pleasing series of drag racing accidents and pictures of Tapia's family and cars, including his twin brother Bobby Tapia, a famous drag racer.
Tapia went on to describe many of the experimental cars that have been created throughout the years but explained the only design that has been successful was the simple, single-engine slingshot model that has been used since the 1950s.
Tapia used various math and physics formulas to prove that any possible math errors and human errors would be negligible to the outcome of the top speed reached.
star.txstate.edu /03/04/10/news5.html   (529 words)

  
 Drag
It is defined as the sum of parasitic drag and induced drag.
This drag is the drag that you referred to as being proportional to speed.
Drag force depends on velocity, frontal area, and the drag coefficient.
www.newton.dep.anl.gov /askasci/phy00/phy00107.htm   (601 words)

  
 PlanetPhysics: airship optimal control, 2D with drag
Unlike the 1D case, which uses the absolute value, the direction of the drag force in 2D is taken into account by the magnitude of the velocity times the component velocities such that the x and y components of the drag force are
"2D with drag airship optimal control" is owned by bloftin.
This is version 1 of 2D with drag airship optimal control, born on 2006-07-25.
planetphysics.org /encyclopedia/2DWithDragAirshipOptimalControl.html   (142 words)

  
 Drag Force - Advanced Physics Forums   (Site not responding. Last check: 2007-10-16)
A graph of Drag Force as a function of velocity is drawn.
drag force is as the name suggests a response of the environment.
THere are initial two force on the system, The weight and the drag force but as the time increases these forces evetually balance each other after which no work is done on the body because there is no force on it.
www.advancedphysics.org /forum/showthread.php?t=3432   (282 words)

  
 Physics - Numericana
Physical Units: A tribute to the late physicist Richard P. Feynman (Nobel 1965).
The Physics Factbook by the students of Glenn Elert at Midwood High School.
In the presence of a drag force F (in a direction opposite to that of the velocity), there's a loss of total energy equal to the power FV of the drag force.
home.att.net /~numericana/answer/physics.htm   (4879 words)

  
 Problems
drag is proportional to the square of speed.
The building is tall enough that aerodynamic drag is should be considered.
The drag force was measured at three different wind speeds while coasting and while pedaling.
hypertextbook.com /physics/matter/drag/problems.shtml   (375 words)

  
 Prograde and Retrograde Gravity Drag? - Advanced Physics Forums
I was looking at a picture of Saturn’s rings today, and very basic question occurred to me. Not all, but nearly all moons orbit in the direction of the rotation of their planet.
A retrograde satellite is going to drag the tidal bulge backwards across the rotation of the planet, so it\'ll have greater effects, I think.
The orbit that has the greatest land speed is the least stable of all orbits and the highest action-reaction tidal drag.
www.advancedphysics.org /forum/showthread.php?t=1715   (1072 words)

  
 Peter Sprunger
During the summer of 2001 I investigated the drag force of propellers using the wind tunnel owned by the Goshen College Physics Department.
For lower pitches, there is more drag on a windmilling propeller and at higher pitches there is more drag on a stationary propeller.
Notice that for the pitch 8 propeller, at longer lengths there is more drag on a stationary propeller than on a windmilling one, but at shorter lengths it is the other way around.
www.goshen.edu /physics/PropellerDrag/PropellerDrag.htm   (451 words)

Try your search on: Qwika (all wikis)

Factbites
  About us   |   Why use us?   |   Reviews   |   Press   |   Contact us  
Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.