the movement It is the change of position of the body from one place to another. Movement may be divided into three types in general:

• Rotational motion – such as the Earth’s rotation around its axis.
• displacement motion – moving an object without changing its direction, such as a car traveling on a straight road.
• Oscillation of a simple pendulum clock.
• Pistol bullet curve movement

Movement has a direction and is therefore a “vector quantity”, for example, it may be horizontal, vertical, east, west, etc.

It defines the distance traveled during the motion of an object offset.

the movement[عدل]

Opportunity The position of the body in space – and is determined by the “location vector” from the point of its unit principle (distance).
the movement It changes the position of the body from one place to another, and its unit (distance / time). Movement causes a change in position called displacement and its unit is distance.
movement rate Its unit is speed (distance/time).
Kinesiology Or kinematics or kinematics is the study of the form of motion, that is, the description of the trajectory of each moving particle.
Speed ​​rate The unit of acceleration is called distance/time squared.
animatronics It is the study of the causes of motion, that is, the description of the forces that cause velocity.

Speed ​​is defined as the distance traveled (displacement) divided by the time:

$\displaystyle v=\frac x\,t\,\,$

Speed ​​can be measured in units, for example how many hoursor miles/houror meters/sec. It is also moving or moving from one place to another.

Acceleration / acceleration[عدل]

acceleration is the time rate of change of velocity

$\displaystyle a=\frac v\,t\,\,$

Acceleration is measured using units such as: meter per second squared Andfeet per second squared.

Effect of body size and weight[عدل]

With regard to the size or weight of the body, if the body is very small compared to the distances traveled, there is no mathematical problem. But if the body is large, then it has a point called the center of gravity, where its movement can be considered as applying to the entire body.

If the body rotates, it is appropriate to describe its motion as a rotation around an axis that passes through a center of gravity, which is a vector quantity m/s

outdated definitions[عدل]

Definitions of the Ikhwan al-Safa[عدل]

in a Fourth century AH (Tenth AD) The Ikhwan al-Safa were known in their letters Movement and stillness ^[1] as it is A form that the soul made in the body after the form, and that stillness is the lack of that form; Stillness in the body is more important than motion, because a body has directions, and it cannot move to all its directions at once, and its movement is not to a direction that is more important to it than movement.

The Ikhwan al-Safa divided the movement into six aspects:

• Universe : It is the emergence of a thing from non-existence into existence, or from power to action.
• Corruption: It is the end of the thing from existence to non-existence .
• the increase : It is the spacing of the ends of the body from its center.
• Decrease: It is the convergence of the ends of the body to its center .
• the change : It is the change of attributes to what is described in terms of colours, tastes, smells and other attributes.
• The shift: As for the movement that is called the shift, it is according to the majority of people the departure from one place to another. As for the one that rotates, it is not valid, because the one that moves in the rotation moves from one place to another, and does not become in another alignment in a second time. It stays in it and does not move. So let the one who says this saying and thinks this thought or estimates that this opinion is correct, know that the center is only an imaginary point and it is the head of the line, and the head of the line is not the place of the part of the body. It should also be known that the one that is moving in a circle with all its parts is moving, and it does not move from one place to another, and it does not become aligned with something else in a second time. As for movement on a straight line, it can only be by moving from one place to another and passing parallels in a second time..

Definitions of Ibn Malaka al-Baghdadi[عدل]

swears son of a king movement in his book Considered wise into two types, natural and forced:^[2]

“And coercion is preceded by natural, because what is restricted is restricted from its nature to a compelling nature.” In this sense, Ibn Malka includes the movement in the upper sphere with that of earthly gravity, i.e., within the natural movement, given that both of them follow a divine law in their movement. As for the forced movement, it is under the influence of coercive force.

Definitions of Ibn Sina[عدل]

And about forced movement displays Ibn Sina in his book healing Six things related to the movement of the shift are:^[3]

• Mobile: moving body
• the engine : The thing that triggers and causes movement
• The engine and its contents: body position
• The engine and its components: The starting position of the movement
• Engine etc: The end position of the movement
• time: The time period for the movement

Rotational motion[عدل]

and consider Rotational motion Another simple type of movement. If an object has a constant velocity but its acceleration is always at right angles to its velocity, it will move in a circle. The required velocity is directed towards the center of the circle and is called centripetal acceleration. For an object moving at speed

$\displaystyle v$

in a circle of a certain radius

$\displaystyle r$

The gravitational acceleration will be:

$\displaystyle a_c=\frac v^2\,r\,\,$

In this, the Ikhwan al-Safa mentions: And know that many people of knowledge have thought that the one moving in a straight line moves many movements, because in its movement it passes many parallels in the state of its movement, and it should not be considered as many movements because of the many parallels, because the arrow in its passage until it makes one movement passes through many parallels, and so does the moving one. On turning, his movement is one until he stands, even if he turns many turns.

Other types of movement[عدل]

ballistics[عدل]

Another simple type of motion that is always noticed is when a ball is thrown at a certain angle in the air. Due to gravity, the ball experiences a constant downward acceleration that reduces its original velocity which should be upwards and then increases its velocity downward as the ball falls to the ground. At the same time, the horizontal component of the original velocity remains constant (ignoring air resistance) causing the ball to move at a constant velocity in the horizontal direction until it hits the ground. The horizontal and vertical components of motion are independent of each other and can be analyzed separately. And the path of the ball resulting in the form of an ellipse.^[4]

Fixed speed[عدل]

There are special types of movement that are easy to describe. First, the speed may be constant. In the simplest case, the velocity may be zero, so the situation will not change during the time period. And with constant velocity, the average velocity is equal to the velocity at any given time. If the time – it is denoted by the symbol (n) – It is measured in hours starting when it is (N)=0then the distance will be – and is denoted by the symbol (f) – Which cuts at a constant speed – and is symbolized by the symbol (pbuh) equal to the sum of the velocity and the time. q = p n ^[4]

Regular wheel[عدل]

In the second special type of locomotion, the wheel is stationary. Since velocity changes, instantaneous velocity or the velocity that occurs at a particular time must be defined. For the fixed wheel (c) which starts at zero velocity, then the instantaneous velocity will at some point be equal to the following value: p = c n
The distance traveled during this time will be: P = 1/ 2 c n2 ^[4]

An important feature noted in this equation is the dependence of the distance on the squared time (n2). A heavy body that falls freely is subjected near the surface of the earth to a constant acceleration. In this case, the acceleration would be 9.8 m/s squared. At the end of the first second, a ball will fall, for example, a distance of 4.9 meters (16 feet) and its speed will be 9.8 meters/second (32 feet/second). At the end of the other second, the ball will fall 19.6 meters, and its velocity will be 19.6 m/sec.

Parachuting[عدل]

The invention of the parachute jump from airplanes was for military purposes because military forces could be landed anywhere in the air. The role of the parachute in its old classic form is to stop the acceleration so that the speed of the parachute jumper is fixed, and he reaches the ground safely, as if he jumped from a height not exceeding four meters. Of course, modern parachutes have modern technologies that enable the jumper to control the parachute in a large way and with extreme accuracy.

Reference[عدل]

In Commons, photos and files for: movement

• Mechanical engineering portal
• Physics portal

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