why does wind resistance make a feather fall slower?
400487
Wind resistance acts as a force which opposes the motion of the feather down to the ground.  The feather's weight acts to accelerate it downward.  You have two opposing forces, one is constant (the weight), the other depends largely on the speed of the feather falling (wind resitance).\n\nThe feather will intially start out accelerating downward due to gravity at -9.81 m/s^2, but as its velocity increase, the opposing force increases aswell, eventually reached an equilibrium with the feather's weight and the object stops accelerating.  Just because there is no acceleration doesnt mean there is no motion, the feather will continue to fall at a constant velocity after the wind resistance has increased enough to counter act the wieght (net force = 0, acceleration = 0).\n\nnet Force = mass * acceleration
309904
There is a speed at which a falling object can't fall any faster, because the wind resistance holds it back.  It's called "terminal velocity".  It's different for a rock and a wad of paper the same size.  The terminal velocity for a raindrop is pretty low.
506884
This design cant pull enough air down fast enough to achieve lift. The key to flight is the airfoil shape of the wing or helo propeller. Its naturally causes high pressure under the airfoil as air moves rapidly over it. Thats where lift is achieved.
1175019
In general resistance increases.If there is no turbulence then it can be shown that viscous drag on a spherical moving body of radius r and velocity v is \n6*pi*(eta)*r*v\nwhere eta is coefficient of viscosity.\nTherefore air resistance is usually taken as directly proportional to velocity.\nHowever in real life things are not that simple.With turbulence various other forces come in play.Surprisingly it can reduce the air drag too.Though it may cause deviations in path as forces are no longer just opposite to velocity .
394186
No, wind is caused since warm ail is less dense than cold air. cold goes to warm, causing wind. If all air was the same temperatureair would sit still unless something moved it (fan etc.)
401274
so if a butterfly flaps its wings it creates a tiny bit of wind, right? the theory is that if that butterfly creates that bit of wind, it changes the strength of the wind overall, and so alters the weather, and the weather alters peoples' plans and the survival of species and a million other things... \n\nit's one way of saying that nothing is so insignifigant that it doesn't make a difference, and the smallest things can still have huge impacts. it's a metaphor for chaos theory.\n\ni reccommend the second link, it's more fun. wikipedia is more informative, though.
1151411
Objects of different mass do fall at the same speed, but air resistance hinders this fact.  For example, if you drop a bowling ball and a feather at the same time on the Earth, obviously the bowling ball falls faster. \n\nHowever, on the moon, when the astronauts dropped a feather and a bowling ball, they hit the ground at the same time. \n\nIt would seem that the bowling ball should fall faster since gravity is pulling on it with more force. But, with the more mass, comes more inertia, which meas it resists being pulled more than the feather. So, the feather is pulled less, but it resists less as well, so because of that, they will fall at the same time. The relationship between the force of pull and the object's inertial compensates exactly so that all objects fall at the same rate.
292689
On extremely cold days many birds will roost to conserve heat. If they take to the air they expose their underwings and bodies, and the short insulating feathers under the flight feathers are exposed to the cold air, so they no longer provide adequate insulation.
595526
The Magnus effect is the name given to the physical phenomenon whereby an object's rotation affects its path through a fluid, in particular, air. It is a product of various phenomena including the Bernoulli effect and the formation of boundary layers in the medium around moving objects.\n\nA spinning object creates a kind of whirlpool of rotating air about itself. On one side of the object, the motion of the whirlpool will be in the same direction as the windstream that the object is exposed to. On this side the velocity will be increased. On the other side, the motion of the whirlpool is in the opposite direction of the windstream and the velocity will be decreased. The pressure in the air is reduced from atmospheric pressure by an amount proportional to the square of the velocity, so the pressure will be lower on one side than the other causing an unbalanced force at right angles to the wind.\n\nThe overall behaviour is similar to that round an aerofoil  with a circulation which is generated by the mechanical rotation, rather than by aerofoil action.\n\nThis is not the only thing causing the deflection of the object. In addition to the Magnus force, the boundary layer of the flow is delayed on the side that is moving in the same direction as the free stream flow, and is advanced on the side moving against the flow. The flow is deflected away from the side moving against the flow, and this momentum change in the flow is balanced by a momentum change in the object in the opposite direction. Anything that disrupts the boundary layer will therefore tend to straighten out the trajectory. This is the reason for dimples on a golf ball: They disrupt the flow around the ball and tend to lessen the effects of spin, as well as helping to reduce pressure drag due to early flow detachment
426165
Birds could fly with only 1 wing if if was "falling" in one direction, if not, then it can not fly. \nHuman Nature, people always want to be better than each other
454243
Your bones are too dense. \n\nNo joke, the reason birds are capable of flight is due to having hollow bones, making them far lighter.
622176
would depend on the mass, and air resistance of the arrow. as arrows have most of their weight at one end I guess they will fall very weell, and with quite low air resistance. a guess would be well in excess of 200 mph, a diving bird of prey can get close to this and an arrow wil have a much smaller profile, but as speed increses the gai you get will diminish. you could try putting numbers in a simulator online if you have some.(like this one below)
517904
You can call it wind resistance or skin friction.
815485
If it's the air pressure outside the ball that you are asking. The higher the air pressure or atmospheric pressure the "heavier" the air is. So kicking a ball into heavy air would slow it down, (resistance). Kicking into lighter air there will be lower resistance.\n Now if its the air pressure in the ball. The harder the ball and the swifter the kick it will travel futher.
841193
It's the fall velocity at which air resistance exactly balances gravitational force, so the falling object no longer accelerates. However, it varies with air density, which changes as the falling object's altitude declines. Gravitational force also changes with altitude because it depends on the distance to the earth's center. As a result, a falling object is hardly ever going to fall at exactly its terminal velocity, since it has to "chase" the changing value of that velocity.
59236
Aircraft are able to climb and maintain altitude by utilizing a combination of the Bernoulli effect and simple momentum transfer in the air flow to generate lift. Lift is generated primarily by the wing of the aircraft. \n\nTo generate lift using the Bernoulli effect, the cross-section of the wing is shaped in such a way that the distance from the leading edge to the trailing edge is greater along a path that runs over the wing than under the wing. As the aircraft is propelled forward, air necessarily flows both over and under the wing. Because of the greater distance that air must travel over the wing, the air pressure over the wing is less than the air pressure under the wing. This difference in pressure between the top and bottom of the wing results in a net upward force, or lift, on the wing. This is the Bernoulli effect. \n\nOne way of understanding the physical basis of the Bernoulli effect is to consider that, since the path of the air flow over the wing is longer, the air over the wing is forced to expand into a greater volume than that flowing under the wing. Consequently, the air pressure over the wing is necessarily lower than that under the wing. \n\nLift can also be generated by dynamic momentum transfer from the airstream. In this method, the tilt, or angle of attack, of the wing relative to the overall direction of motion causes the flow of air striking the under surface of the wing to be turned, or deflected, downward. That is, a downward momentum is imparted to the airflow by the deflection induced by the wing. Newton's law dictates that a compensating reaction force (lift) acts in the upward direction on the wing according to F = dp/dt, where p is the momentum (F and p are vectors). This is the same principle that generates sufficient upward force on water skis to keep a skier from sinking below the surface. \n\nIn practice, the aerodynamics of flight are complicated by many other effects. Obviously, opposing the upward lift is the downward force of gravity. Likewise, opposing the forward thrust of the aircraft is the backward force of drag created by resistance to passage through the air. Also, both the Bernoulli and momentum transfer effects depend upon the smooth, or laminar (streamline), flow of air around the wing. Various factors can induce turbulence in the air flow that (generally) spoils lift, increases drag and decreases the overall efficiency of the aircraft in flight. \n\nFor more details, see the web site: \n\nhttp://www.aviation-history.com/theory/index-theory.html
664707
The terminal velocity of an object falling towards the ground, in non-vacuum, is the speed at which the gravitational force pulling it downwards is equal and opposite to the atmospheric drag (also called air resistance) pushing it upwards. At this speed, the object ceases to accelerate downwards and falls at constant speed. An object moving downwards without power at greater than the terminal velocity (for example because it previously used power to descend, it fell from a thinner part of the atmosphere or it changed shape) will slow down until it reaches terminal velocity.\n\nFor example, the terminal velocity of a skydiver in a normal free-fall position with a closed parachute is about 195 km/h (120 Mph). It would take about 5.5 seconds to reach that speed. This speed increases to about 320 km/h (200 Mph) if the skydiver pulls in his limbs—see also freeflying. This is also the terminal velocity of the Peregrine Falcon diving down on its prey.\n\nThe reason an object reaches a terminal velocity is because the drag force resisting motion is directly proportional to the square of its speed. At low speeds the drag is much less than the gravitational force and so the object accelerates. As it speeds up the drag increases, until eventually it equals the weight. Drag also depends on the cross-sectional area. This is why things with a large surface area such as parachutes and feathers have a lower terminal velocity than small objects like bricks and cannon balls.