Introduction to Engineering Mechanics - Vocabulary Flashcards

Vocabulary flashcards covering core concepts, vector classifications, statutory definitions, and force analysis principles from the Introduction to Engineering Mechanics (MEC1101) course lecture notes.

Engineering Mechanics

The physical science that studies the state of rest or motion of bodies under the action of forces.

Statics

The branch of mechanics that deals with bodies at rest or in equilibrium, focusing on forces acting on stationary bodies.

Dynamics

The branch of mechanics that deals with the motion of bodies, considering forces, velocity, acceleration, and time.

Space

The geometric region occupied by bodies, where positions are described using linear and angular measurements relative to a coordinate system.

Time

The measure of the succession of events, serving as a basic quantity in dynamics.

Mass

A measure of the inertia of a body or its resistance to changes in motion, which is independent of position or motion.

Force

The action of one body on another, characterized by magnitude, direction, and point of application.

Concentrated Force

A force assumed to act at a single point, used as an idealization when the contact area is very small compared with the dimensions of the body.

Distributed Force

A force distributed over an area, length, or volume, whose intensity is expressed as force per unit area, length, or volume.

Moment

The tendency of a force to rotate a body about an axis or point.

Couple

The tendency of two equal, opposite, and non-collinear forces to rotate a body.

Torque

An alternative term commonly used for a moment and/or couple.

Scalar Quantities

Quantities that possess magnitude only, such as time, volume, density, speed, energy, and mass.

Vector Quantities

Quantities that possess both magnitude and direction, such as displacement, velocity, acceleration, force, moment, and momentum.

Fixed Vector

A vector that acts at a fixed point.

Sliding Vector

A vector that can move along its line of action.

Free Vector

A vector that can be moved without changing its effect.

Equal Vectors

Vectors that have the same magnitude and direction.

Negative Vector

A vector that has the same magnitude as another vector but acts in the opposite direction.

Coplanar Vectors

Vectors that lie in the same plane.

Concurrent Vectors

Vectors whose lines of action meet at one point.

Collinear Vectors

Vectors that have the same line of action.

Parallelogram Law of Vector Addition

A law stating that two vectors $V_1$ and $V_2$ can be replaced by an equivalent resultant vector $V$ given by $V = \sqrt{V_1^2 + V_2^2 + 2 V_1 V_2 \cos(\theta)}$, represented by the diagonal of the parallelogram formed by $V_1$ and $V_2$.

Free Body Diagram (FBD)

A drawing that shows all external forces and moments acting on an isolated body.

Constraint

Any restriction that prevents or limits the movement of a body, producing support reactions to maintain equilibrium.

Lami's Theorem

A theorem stating that if a body is in equilibrium under the action of three concurrent forces, each force is proportional to the sine of the angle between the other two forces, expressed as $\frac{P_1}{\sin(\gamma)} = \frac{P_2}{\sin(\beta)} = \frac{P_3}{\sin(\alpha)}$.

Statically Determinate

A system that has the minimum necessary constraints, where support reactions can be calculated using equilibrium equations alone.

Statically Indeterminate

A system that has more constraints than necessary, requiring additional equations or information beyond equilibrium equations to solve.

Redundant Support

A support that can be removed without losing equilibrium, which creates an extra unknown reaction.