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The Science of Soccer is a fascinating book, dealing with a wide range of subjects where scientific analysis can be applied to football. Starting with a qualitative. Soccer is very most popular in Europe and American. It has vivid and interesting history in the world of sports. Early evidence of soccer being.
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Send Feedback. It is also an endless scientific panorama. Every movement by the players and each interaction with the ball involves physics, fluid mechanics, biology, and physiology, to name just a few of the scientific disciplines. In a book that targets middle and high school players, Taylor begins with a history of soccer and its physical and mathematical aspects.
He then addresses important questions such as how and why a ball bounces, how the ball spins, and what these dynamics mean for the game. He introduces readers to the science of kicking, heading, and trapping and looks at the sources of the energy required to run, jump, and kick for an entire game. Taylor then puts it all together by following a sequence of plays and describing the science behind tactical maneuvers.
Similarly, to accelerate an object by 10g, for example, requiresa force equal to 10 times its weight. The distance thrown is generally notgreat and the required accuracy is easily achieved by anyplayer. To reach the goal-area calls for athrow approaching 30 yards, and long throws of this typeoften become a speciality of players with the necessaryskill. A short throw of, say, 10 yards needs a throw speed ofaround 20 miles per hour. Taking a hand movement of 1 footthe required force is typically 10—15 pounds. In the absence of airresistance this challenging throw would require the ball to bethrown with a speed of 40 miles per hour.
Throw to centre of the pitch. Throwing, heading, catching 35hour. To give the ball such a high speed the thrower mustapply a large force over as long a path as possible.
Althougha short run up to the throwing position is helpful, both feetmust be in contact with the ground during the throw. Thislimits the distance the arms can move. The back is initiallyarched with the ball behind the head, and the muscles of thebody and arms are then used to push the ball forward andupward.
For a long throw the ball remains in contact withthe hands over a distance of about 2 feet. Since the ball weighs approximately apound this means that the average force on the ball must beabout 34 pounds; the maximum force will of course be some-what larger. The record for the longest throw was achieved by theAmerican college player Michael Lochnor, who threw theball The record was previously held byDavid Challinor of Tranmere Rovers who reached Theball can be quite accurately rolled or thrown to a nearbycolleague. Sometimes the goalkeeper chooses to hurl the balltoward the half-way line rather than kick it, and an impressiverange can be obtained in this way.
Despite the use of only onearm these throws can carry farther than a throw-in. This ispartly because of the longer contact with the ball during thethrow, allowing the force to be applied for more time, andpartly because of the greater use of the body muscles.
Thegreater ease of obtaining the optimum angle of throw for along range is probably another factor. For a long throw thehand remains in contact with the ball for about 6 feet, andthe contact time for the throw is typically several times aslong as for a throw-in. The types ofheader are characterised by the way in which momentum istransferred between the head and the ball. When a defender heads away a long ball his neck isbraced and the bounce of the ball from his head transfersmomentum to his body.
Another situation in which momen-tum is taken by the body is in the diving header. In this casethe whole body is launched at the ball and it is the speed ofthe body which determines the resulting motion of the ball. In more vigorous headers the muscles are used to thrustthe head at the ball. This type of header is commonly usedby strikers to propel a cross from the side of the pitchtoward the goal. When the head strikes the ball, momentumis transferred to the ball and the head is slowed. In heading the ball the movement of thehead is restricted to a few inches, and the velocity given tothe ball is much less than that possible for a kick.
Sometimes the head is struck by an unseen ball, or beforethe player can prepare himself. In asevere case of a 50 mile per hour ball, the head could bemoved an inch in a hundredth of a second, the force on thehead corresponding to an acceleration of 50g. Accelerationslarger than this can lead to unconsciousness. The punchWherever possible, goalkeepers aim to take charge of a ballclose to goal by catching it.
There are two circumstanceswhere this is not possible. Firstly there is the ball which is If he can he will then punch the ball as far awayfrom the goal as possible. When the punchfollows a dive by the goalkeeper, considerable accuracy iscalled for because of the brief time that a punch is possible. For example, a ball moving at 50 miles per hour passesthrough its own diameter in one hundredth of a second. While the punch is usually the prerogative of the goal-keeper, it is also possible to score a goal with a punch.
Figure 3. The catchGoalkeepers make two kinds of catch. The simpler kind is thecatch to the body. In this case most of the momentum of theball is transferred to the body. Because of the comparativelylarge mass of the body the ball is brought to rest in a shortdistance. The goalkeeper then has to trap the ball with hishands to prevent it bouncing away. In the other type of catch the ball is taken entirely with thehands.
With regard to the mechanics, this catch is the inverse ofa throw. The ball is received by the hands with its incomingspeed and is then decelerated to rest. During the decelerationthe momentum of the ball is transferred to the hands andarms through the force on the hands. The skill in this catch isto move the hands with the ball while it is brought to rest. Too small a hand movement creates a too rapid deceleration Maradona bending the rules.
The movement of the hands during the catch isnevertheless usually quite small, typically a few inches.
The catch iscompleted in just over a hundredth of a second. ReceivingWhen a pass is received by a player the ball must be broughtunder control, and in tight situations this must be done Throwing, heading, catching 39without giving opponents a chance to seize the ball.
The basicproblem with receiving arises when the ball comes to theplayer at speed. If the ball is simply blocked by the foot, itbounces away with a possible loss of possession. The ball iscontrolled by arranging that the foot is moving in the samedirection as the ball at the time of impact.
The mechanicsare quite straightforward — essentially the same as for abounce, but with a moving surface. To receive a fast ball successfully it is not only necessaryto achieve the correct speed of the foot, but also requires goodtiming. TrappingTrapping the ball under the foot presents a similar challenge tothat of receiving a fast pass in that the time available is verybrief.