Research An object that is falling through the atmosphere is subjected to two external forces. The first force is the gravitational force, expressed as the weight of the object. The weight equation which is weight (W) = mass (M) x gravitational acceleration (A) which is 9. 8 meters per square second on the surface of the earth.
The gravitational acceleration decreases with the square of the distance from the center of the earth. If the object were falling in a vacuum, this would be the only force acting on the object. But in the atmosphere, the motion of a falling object is opposed by the air resistance or drag. The drag equation tells us that drag is equal to a coefficient times one half the air density (R) times the velocity (V) squared times a reference area on which the drag coefficient is based. The motion of a falling object can be described by Newton’s second law of motion, Force = mass x acceleration. Do a little algebra and solve for the acceleration of the object in terms of the net external force and the mass of the object (acceleration = Force / mass).
The net external force is equal to the difference between the weight and the drag forces (Force = Weight – Drag).
The acceleration of the object then becomes acceleration = (Weight – Drag) / mass. The drag force depends on the square of the velocity. So as the body accelerates, its velocity (and the drag) will increase. It will reach a point where the drag is exactly equal to the weight. When drag is equal to weight, there is no net external force on the object, and the acceleration will become equal to zero.
The Essay on Biomechanics Of Tennis Force Ball Object
Bio-mechanical Principles of the Serve Bio-mechanics is the science that looks at the internal and external factors acting on the human body and the effects produced by these factors. Bio-mechanics studies what makes a body move and the results of that movement. The two main principles of the tennis serve are motion and force. Motion is the "continued change of position of an object in space" ...
The object will then fall at a constant velocity as described by Newton’s first law of motion. The constant velocity is called the terminal velocity. What is aerodynamics? The word comes from two Greek words ae rios concerning the air, and dynamic, meaning powerful. Aerodynamics is the study of forces and the resulting motion of objects through the air. Humans have been interested in aerodynamics and flying for thousands of years, although flying in a heavier-than-air machine has been possible only in the last hundred years. Aerodynamics affects the motion of a large airliner, a model rocket, a beach ball thrown near the shore, or a kite flying high overhead.
The curve ball thrown by big league baseball pitchers gets its curve from aerodynamics. If both friction and air resistance were eliminated from acting on the swinging pendulum, would gravity act on the pendulum to slow it down and eventually stop? If all friction and air resistance was eliminated (plus, the losses due to deformation of the string and the like) the pendulum, under ONLY the effect of gravity, would keep swinging indefinitely. This is because gravitation is a ‘conservative’ force; it does not drain any energy from the object moving under it, it just converts the energy from one form to another. When the pendulum reaches either end at its highest point, all the energy is potential energy, and the kinetic energy is zero. At the bottom of the swing, the kinetic energy is maximum, while potential energy is minimized. No energy is transferred out of the system, so it must keep moving.
In the presence of friction, however, energy is removed from the system in the form of heat. (The air heats up a little and the contact point of the string heats up a little).
What is air resistance? Basically, it is friction between an object and the air. What causes air resistance? All matter is made from atoms and / or molecules. The air is no exception. When something moves through the air, it bumps into the atoms and molecules.
The Essay on Chuck Yeager Air Force Pilot
Chuck Yeager is unquestionably the most famous test pilot of all time. He won a permanent place in the history of aviation as the first pilot ever to fly faster than the speed of sound, but that is only one of the remarkable feats this pilot performed in service to his country. Charles Elwood Yeager was born in 1923 in Myra, West Virginia and grew up in the nearby village of Hamlin. Immediately ...
Take for example a car: Air particles hit the front of the car as it travels through the air. Even though atoms and molecules are very tiny and light, each collision causes a force on the moving object (the car).
The force from each individual collision is, therefore, very tiny. There are however millions of these collisions each second, so millions of tiny forces add up to make a large overall force. All of these little forces, all in the same direction, equal one big force. This big force is called air resistance.
What happens to the size of the air resistance force as the speed increases? If the car is going faster, then it will hit the atoms and molecules of the air harder. This means that the tiny forces will be bigger. This in turn means that the air resistance force gets bigger as something moves faster. This can be felt happening when walking and running.
When walking, unless it is windy, one does not normally notice the air resistance because it is very low (collisions are not very hard).
When running, one can readily feel the air resistance on the face. It has already been established that for a ball falling through water, Aristotle’s description is closer to the truth than Galileo’s ‘naturally accelerated motion’. Galileo was well aware of that, and his response was that the true natural motion could only take place in a vacuum, otherwise, the medium the body was falling through would impede the acceleration to some degree. Galileo’s insight was that for a reasonably heavy body falling a few meters through air, the air resistance did not make a big difference. He did state explicitly, though, that even for heavy materials, air resistance was important at the speeds attained by firearms.
In practice, as Galileo understood, the air resistance of a falling object increases with speed. But he did not think in terms of forces, and the force of gravity, the weight, pulling the ball down. So he thought that since a ball of wood was more slowed in its fall by air resistance, than a ball of lead of identical size and shape, the ball of wood must be experiencing a greater retarding force. It is now understood that the drag force is the same, but since the lead weighs more, the same drag force is relatively less important to the heavier ball. Actually, the dependence of drag force on speed is quite a complicated subject. For a ball falling slowly through a viscous fluid, the force is proportional to the speed.
Descriptive Essay on Air Force One
Head of State Throughout history there have been many valiant, intrepid, superhuman heroes who usually have superpowers, rescue the girl of his dreams and save the day. These heroes often become too predictable and it is almost as if the same story is being retold time and again. This hero however does not have superhuman strength, cannot fly nor does he save a damsel in distress. He is simply a ...
Imagine a steel ball falling through molasses. This kind of smooth flow leaves no ‘wake’, there is no turbulence. Parachutes are a great help to man. Today they are used not only during times of war, but they are also used for dropping food and medical supplies into areas stricken by disasters such as floods and earthquakes. Life rafts and other survival equipment are lowered by parachute in air-sea rescue operations.
Parachutes also serve as landing breaks for high speed jet airplanes, (such as those that take off and land on the decks of aircraft carriers), and they are used to slow a returning space capsule as it re-enters the Earth’s atmosphere. Parachutes work because of something called ‘air resistance.’ If there were no air resistance, then gravity would cause everything to fall at the same rate, so no matter what item were dropped, (i. e. a feather or a rock), it would hit the ground at exactly the same time (assuming it were dropped from the same height).
But air resistance complicates these things (and makes sky-diving a lot more fun).
Air resistance happens because as things fall, they have to push their way past the atoms and molecules that make up air in order to get where they are going.
For something like a rock, this is not really a big deal, since rocks tend to be really heavy while being pretty small, so they can push the air molecules out of the way quite easily. But things like feathers can not push the air molecules out of the way very well – for one, they weigh less so they do not push as hard, and for another, they are pretty big, so they run into a lot more air molecules than the rock does. So the air actually slows the feather down. This is what makes a parachute work. If a person were to fall without a parachute they would push the air molecules out of the way very easily, so the air would not be able to do much to slow the person down. But if the person is attached to a parachute, then the parachute will run into lots of air molecules, and especially if it is curved to be higher up in the middle, it will be very hard for the air molecules to get out of the way.
The Term Paper on Web Services part 1
Web Services. Web Services are not implemented in a monolithic way, but rather represent a collection of several related technologies. A new language was developed in the Internet back in 1999. What were the reasons for that? The old one was called HTML, and it was a gear for the whole internet, especially for the area called World Wide Web, development process. Now the Web outgrew its creator and ...
If they can not get out of the way, they will slow the parachute (and hence the person) down. Bibliography web (10/13/04) web (10/13/04) web (10/13/04) web (10/13/04) web and in the Air/Air Resistance/20020326210816. htm (10/13/04) web resistance. htm (10/13/04).
