2.1 Centroids, Vectors, and Joints

Question 1

Cable

Answer 1

a strong rope, usually made of metal, designed to have great tensile strength and to be used instructures.

Question 2

Centroid

Answer 2

the geometric center of an area

Question 3

Compression Force

Answer 3

a body subjected to a push

Question 4

Concurrent Force Systems

Answer 4

A force system where all of the forces are applied at a common point on the body or having their liens of action with a common intersection point.

Question 5

Cross-Section Area

Answer 5

A surface or shape exposed by making a straight cut through something at a right angle to the axis

Question 6

Direction

Answer 6

the direction of a vector is defined by the angle between a reference axis and the arrow’s line of direction.

Question 7

Fixed Support

Answer 7

a support that prevents translation and rotation in a beam.

Question 8

Flange

Answer 8

a broad ridge or pair of ridges projecting at a right angle from the edge of a structural shape in order to strengthen or stiffen

Question 9

Free Body Diagram

Answer 9

A diagram used to isolate a body from its environment, showing all external forces and CONTACT forces acting upon it.

Question 10

Gusset

Answer 10

A plate or bracket for strengthening an angle in framework.

Question 11

Joint

Answer 11

The connection points of members of a truss.

Question 12

Magnitude

Answer 12

The absolute value of a number.

Question 13

Method of Joints

Answer 13

A method of analysis of trusses which constructs free body diagrams of each joint and determines the forces acting in that joint by considering equilibrium of the join pin.

Question 14

Moment

Answer 14

the turning effect of a force about a point equal to the magnitude of the force times the perpendicular distance from the point to the line of action from the force

Question 15

Moment of Inertia

Answer 15

A mathematical property of a cross section that is concerned with a surface area nd how that area is distributed about a centroidal axis.

Question 16

Newton’s First Law

Answer 16

Every body or particles continues at a state of rest or uniform motion in a straight line, unless it is compelled to change that state by forces acting upon it.

Question 17

Newton’s Second Law

Answer 17

The change of motion of the body is proportional to the net force imposed on the body and is in the direction of the net force.

Question 18

Newton’s Third Law

Answer 18

If one body exerts a force on a second body, then the second body exerts a force on the first body which is equal in magnitude, opposite in direction , and collinear

Question 19

Pinned Support

Answer 19

A support that prevents translation in any direction

Question 20

Planar Truss

Answer 20

A truss that lies in a single plane often used to supports roofs and bridges

Question 21

Resultant Force

Answer 21

The resultant of a system of force is the vector sum of all forces.

Question 22

Roller Support

Answer 22

A support that only prevents a beam from translating in one direction

Question 23

Scalar

Answer 23

A physical quantity that has magnitude only

Question 24

Simple Truss

Answer 24

a truss composed of triangles, which will retain its shape even when removed from supports.

Question 25

Static Equilibrium

Answer 25

A condition where there are no net external forces acting upon a particle or rigid body and the body remains at rest or continues at a constant velocity

Question 26

Statically Indeterminate

Answer 26

A structure or body which is over-constrained such that there are more unknown supports than there are equations of static equilibrium

Question 27

Structure

Answer 27

something made up of interdependent parts in a definite pattern of organization such as trusses, frames, or machines

Question 28

Tension Force

Answer 28

A body subjected to a pull

Question 29

Vector Quantity

Answer 29

A quantity that has both a magnitude and direction.