Mechanics Exam 1

UARK Biomechanics

Biomechanics

-the application of mechanical principles in the study of living organisms

-examining the forces acting on and within a body and the effects of these forces

Mechanics

branch of physics that analyzes the action of forces and particles of mechanical systems

Rigid Body

a system of particles (a body) which does NOT deform

Rigid Body Mechanics

application of mechanical principles to a rigid body system or rigid bodies

Statics

study of rigid bodies or systems that are in a state of constant motion (at rest or moving at a constant speed)

Dynamics

study of rigid bodies or systems that are subject to acceleration

Kinematics

description of motion as a function of space and time WITHOUT reference to forces causing the motion

Kinetics

relationship between forces acting on a rigid body or system and the motion of the rigid body or system

Deformable Body Mechanics

application of the principles of mechanics to a deformable body

Elasticity

propensity of a material to return to its original shape when deformed

Plasticity

propensity of a material to undergo permanent deformation when loaded

Viscoelasticity

material exhibits both viscous and elastic characteristics when deformed

Fluid Mechanics

application of the principles of mechanics to fluids (liquids or gases)

Retilinear

linear motion along a straight line

Curvilinear

linear motion along a curved line

Linear Motion

motion along a line with all parts of the body moving the same distance in the same direction at the same time

Angular Motion

All parts of the body move in a circle about a central line or point (axis of rotation)

What are the three basic quantities? (include SI units)

Length - meters

Mass - kilograms

Time - seconds

What is the difference between linear and angular motion?

linear moves along a line

angular moves around an axis of rotation

What is the difference between rectilinear and curvilinear?

rectilinear moves on a straight line

curvilinear moves on a curved line

What is the difference between distance and displacement?

distance: length of path traveled (scalar)

displacement: difference between initial and final position (vector)

What is the difference between speed and velocity?

speed is scalar (uses distance to calculate)

velocity is vector (uses displacement)

What is the relationship between displacement, velocity, and acceleration?

velocity is the rate of change of displacement

acceleration is the rate of change of velocity

What is propulsion?

acceleration when the magnitude of velocity increases (object speeds up)

What causes breaking?

when the magnitude of velocity decreases (object slows down)

General Motion

A combination of translation and rotation

What is the difference between translation and rotation?

translation is linear motion

rotation is angular motion

Deformable Body

body that changes its shape and/or volume when acted upon by a force