MECH

39問 • 1年前

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Defined as the science which considers the effects of forces on rigid bodies.

Engineering Mechanics

We consider the effects and distribution of forces on rigid bodies which are and remain at rest, or of having constant velocity.

Statics

We consider the motion of rigid bodies caused by the forces acting upon them.

Dynamics

Defined as a definite amount of matter the parts of which are fixed in position relative to each other.

Rigid Body

Defined as that which changes, or tends to change, the state of motion of a body.

Force

To produce stress and deformation in the body on which the force acts.

Internal Effect

Considered in engineering mechanics.

External Effects

Considered in strength of materials.

Internal Effects

States that the external effect of a force on a body is the same for all points of application along its line of action.

Principle of Transmissibility

It is independent of the point of application.

Principle of Transmissibility

Is any arrangement where two or more forces act on a body or on a group or related bodies.

Force System

When the lines of action of all the forces in a force system line in one plane.

Coplanar, Non-Coplanar

Forces whose lines of action pass through a common point.

Concurrent Force Systems

Those in which the lines of action are parallel.

Parallel Force Systems

Those in which the lines of action neither are parallel nor intersect in a common point.

Non-Concurrent Force Systems

The principles of mechanics are postulated upon several self-evident facts which cannot be proved mathematically but can only be demonstrated to be true.

Axioms of Mechanics

The resultant of two forces is the diagonal of the parallelogram formed on the vectors of these forces.

Parallelogram Law

Two forces are in equilibrium only when equal in magnitude, opposite in direction, and collinear in action.

Equilibrium Law

A sketch of the isolated body which shows only the forces acting upon the body.

Free-Body Diagram

The forces acting on the free body.

Applied Forces

Have a size or magnitude only and need no other information to specify them.

Scalar Quantities

Have both a size or magnitude and a direction, called the line of action of the quantity.

Vector Quantities

The process of adding vectors geometrically.

Parallelogram Law

This law says, "Two vectors can be arranged as adjacent sides of a parallelogram such that their tails attach with each other and the sum of the two vectors is equal to the diagonal of the parallelogram whose tail is the same as the two vectors".

Parallelogram Law

States that when two vectors are represented as two sides of the triangle with the order of magnitude and direction, then the third side of the triangle represents the magnitude and direction of the resultant vector.

Triangle Law

Defined as one which does not show the point of application of the vector.

Free Vector

Forces acting at some angle from the coordinate axes can be resolved into mutually perpendicular forces.

Components

Is a force or a couple that will have the same effect to the body, both in translation and rotation, if all the forces are removed and replaced by the resultant.

Resultant of a Force System

Is the measure of the capacity or ability of the force to produce twisting or turning effect about an axis.

Moment

The intersection of the plane and the axis.

Moment Center

The perpendicular distance from the moment center to the line of action of the force.

Moment Arm

States that the moment of a force about any point is equal to the algebraic sum of the moments of the component forces about the same point.

Varignon's Theorem

The effect of a system of forces on a body.

Resultant

The measure of its ability to produce turning or twisting about the axis.

Moment of a Force

The product of the force and the perpendicular distance from the axis to the line of action of the force.

Moment of Force Perpendicular to a Plane

The axis of moments, which is perpendicular to the plane of the forces, appears as a point.

Center of Moments

The term used to designate the condition where the resultant of a system of forces is zero.

Equilibrium

Its physical meaning, as applied to a body, is that the body either is at rest or is moving in a straight line with constant velocity.

Equilibrium

An isolated view of a body which shows only the external forces exerted on the body.

Free-Body Diagram

Enumeration

Sabrina Mikhaela Canindo · 42問 · 1年前

Enumeration