Statics

what are the 3 force characterizaton?

1) point of application 2) its magnitude 3) its direction ( defined by line of action)

sliding vector

Can be moved along a given line collinear with the vector itself

Free vector

Definite magnitude & direction, but no specific location in space

Two vector quantities that we deal with most in this class?

Force and moment

collinear forces

Forces that act along a same line of action , clothes on a clothesline

Bound Vector

Has a specified point of application

Identification of Forces

The first step in dealing with any problem in Mechanics

Magnitude of a Vector

The length of the vector

W=mg=?

Weight= mass of body x acceleration due to gravity

external forces

a force acting on the outside of a structure set in equilibrium

internal forces

a force effect within the entity or any component part of a structure set in equilibrium

what is a force?

a push or pull on an object

What is a vector?

a quantity that has both magnitude and direction and add to the parallelogram law

rigid body?

body of system of particles in which the distance between two particles remain constant. does not change shape

con-current forces

forces that all intersect at a common point.

coplanar forces

forces that all lie in the same plane

what is a scalar?

has only magnitude, not direction

a scalar quantity? mass or weight?

mass

a unit of slug is? mass or weight?

mass

amount of material in a body? mass or weight

mass

measure of inertia? mass or weight

mass

the same in any gravitational field ? mass or wieght? independent or dependent?

mass, independent of location

what is a particle?

model that has a mass but no size

General Space Force System

non-coplaner, non-parallel, non-concurrent, non-collinear force system

concentrated force (load)

represents the effect of a loading which is assumed to act at a point on a body

what is inertia?

the measure of the resistance to a change in motion

a unit of of pounds=newtons? mass or weight?

weight

effect of gravity on a body? mass or weight

weight

vector quantity? mass or weight?

weight

varies with strength of gravitational pull? mass or weight

weight, dependent of loacation

measure of force? mass or weight

weight, exerted on a body by a gravitational field