Force System 2D - Tewodros · PDF file•Categories depending on their arrangement in plane Coplanar collinear forces Definition Cont Coplanar parallel forces Coplanar concurrent forces

Chapter II

Force Systems 2DForce Systems 2D

Definition

• A force can be defined as the action of one body on

another that changes/tends to changes the state of

the body acted on.

• A force can be applied on a body as;

�Contact force:-Applied by direct mechanical contact of �Contact force:-Applied by direct mechanical contact of

the acting body on the acted one (Created by push and

pull).

�Remote action (Body force):-Applied by remote action as

in gravitational, electrical, Magnetic, etc forces.

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• Categories of force depending on their

arrangement in space.

� Coplanar Forces:- are forces which act on the

same plane.

Definition Cont…

same plane.

� Non coplanar forces:- are forces which act on

different planes » Non coplanar parallel forces

» Non-coplanar concurrent forces

» General Non coplanar force


• Categories depending on their

arrangement in plane

� Coplanar collinear forces

Definition Cont…

� Coplanar collinear forces

� Coplanar parallel forces

� Coplanar concurrent forces

� General coplanar forces


• Coplanar collinear forces:- are coplanar forces

acting on the same line-collinear.

• Coplanar parallel forces:- Are forces which are

Definition Cont…

• Coplanar parallel forces:- Are forces which are

on the same plane and parallel


• Coplanar concurrent forces:- Are forces on the

same plane whose lines of action intersect at a

point.

Definition Cont…


• General coplanar forces

Definition Cont…






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Example 2/3

Given vector A with the following properties:

Magnitude= 150, Ɵz =450, Ɵy= 600, and it is known

that Ax is directed in the positive x direction. Express

the vector in Cartesian form.

Example 2/4

Example 2/3

Given vector A with the following properties:

Magnitude= 150, Ɵz =450, Ɵy= 600, and it is known

that Ax is directed in the positive x direction. Express

the vector in Cartesian form.

Example 2/4

Determine a unit vector normal to the plane of the


Determine a unit vector normal to the plane of the

triangle formed by three points: (0,0,2), (2,0,0), and

(0,2,0)as its vertices.

Example 2/3Example 2/

A vector F has a magnitude of 2 and is directed from

point A to point B as shown in the figure below.

Calculate the projection of this vector onto line CD

and determine also the angle between F and CD.

5




Definition

•Moment (torque )

•Tendency of a force to •Tendency of a force to

rotate a body about a

given axis.






























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Couple

• moment produced by 2 equal and

opposite forces is known as a

couple.couple.


Couple Cont…

• Moment of couple about any point

of reference 0.


• Moment of couple about any point of

reference 0.

Couple Cont…


• Moment of couple about any point of

reference 0.

Couple Cont…


Couple Cont…


Couple Cont…

• Resolution of a force into a force and a

couple equal external effect.


Documents

Force System 2D - Tewodros · PDF file•Categories depending on their arrangement in plane Coplanar collinear forces Definition Cont Coplanar parallel forces Coplanar concurrent forces