Motion Dimensions :: 1-D 2-D 3-D

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A body executing translatory motion is such that all the particles of the body are uniformly directed and will have the same speed at any point of time during its motion.

Size of the body in motion

The total mass of a body how much ever large it may be can be assumed to be concentrated at a point called the center of mass of the body.

We can assume a single point in place of the body executing translatory motion, for the purposes of study of motion.

Motion and the three dimensions

Every body executing translatory motion traverses a path. Based on the path traversed by the body, the motion can be classified as

• One Dimensional [1-D]

  Where the path traversed by the body in motion is a straight line, we say its motion is one dimensional.

  Eg:	(1)	A train moving on a straight railway track
  	(2)	An athlete running on a straight track

• Two Dimensional [2-D]

  Where the path traversed by the body in motion is a plane, we say its motion is two dimensional.

  Eg:	(1)	The motion of a coin or striker on the carrom board
  	(2)	The motion of a foot ball player on the ground
  	(3)	The motion of a javelin thrown by an athlete moving without swaying sideways

• Three Dimensional [3-D]

  Where the path traversed by the body in motion is space, we say its motion is three dimensional.

  Eg:	(1)	The motion of electrons in an atom
  	(2)	The motion of a foot ball while in play

Locating and describing the position of a body in motion

Assuming a single point in place of the body we can locate and describing the position of a body at any instance using the cartesian geometry techniques.

This is done by assuming a coordinate system based on the type of motion executed by the body and thereby identifying the position of the body within respect to that coordinate system.

The coordinate system that we assume is dependent on the type of motion that the body is executing. Where the motion of the body is

• One Dimensional
  A Coordinate line is assumed in relation to the path of the body (since the path traversed is a straight line).

  The location of the body is described by the coordinate of the point representing the body. There would be one coordinate describing the location of a body generally identified as x.

• Two Dimensional
  A Rectangular Cartesian Coordinate Plane is assumed in relation to the path of the body (since the path traversed is a plane).

  The location of the body is described by the coordinates of the point representing the body. There would be two coordinates describing the location of a body, the first and the second coordinates generally identified as x and y.

• Three Dimensional
  A Rectangular Cartesian Coordinate Space is assumed in relation to the path of the body (since the path traversed is space).

  The location of the body is described by the coordinates of the point representing the body. There would be three coordinates describing the location of a body, the first, second and the third coordinates generally identified as x, y and z.

Author Credit : The Edifier

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