Module #1, Part 1- Fundamental Concepts and Definitions, Force & Force Systems

Question 1

is an applied science which describes and predicts the conditions of rest or motion of bodies under the action of forces.

is the foundation of most engineering sciences and is an indispensable prerequisite to their study.

Answer 1

Mechanics

Question 2

• Rigid bodies
• Deformable bodies
• Fluids

Answer 2

Categories of Mechanics

Question 3

• Statics
• Dynamics

Answer 3

Categories of Rigid bodies

Question 4

needed to locate the position of a point in space. Distance is described in terms of a standard unit of ___

Answer 4

Length -

Question 5

associated with the notion of the position of a point P given in terms of three coordinates measured from a reference point or origin

Answer 5

Space

Question 6

definition of an event requires specification of the time and position at which it occurred

Answer 6

• Time -

Question 7

used to characterize and compare bodies, e.g., response to earth’s gravitational attraction and resistance to changes in translational motion

Answer 7

Mass -

Question 8

• represents the action of one body on another. A ___ is characterized by its point of application, magnitude, and direction, i.e., a force is a vector quantity.

Answer 8

• Force

Question 9

• 1 ft = __in. (inches).

Answer 9

12

Question 10

• ___ ft = 1 mi. (mile).

Answer 10

5280

Question 11

___ lb = 1 kip (1 kilo-pound).

Answer 11

1000

Question 12

• ___ lb = 1 ton

Answer 12

2000

Question 13

N x 10^9

Answer 13

Giga

Question 14

N x 10^6

Answer 14

mega

Question 15

N x 10^3

Answer 15

kilo

Question 16

N x 10^-3

Answer 16

milli

Question 17

N x 10^-6

Answer 17

micro

Question 18

N x 10^-9

Answer 18

nano

Question 19

The weight of a body, or force of gravity exerted on that body, should also be expressed in ___.

Answer 19

Newton

Question 20

Weight is a __

Answer 20

Force

Question 21

Weight of a body Formula

Answer 21

W= mg

Question 22

g=

Answer 22

9.81 m/s2 (32.2 ft/s2 )

Question 23

on a body is a force generated outside the body (i.e. Load on the body)

Answer 23

External force

Question 24

On a body is a force generated inside the body (to keep the body together

Answer 24

Internal force

Question 25

__ is an external force on the body that tries to change the state of movement of the body.

ex. The force with which the earth attracts a person (the weight of the person)

Answer 25

Applied force

Question 26

is an external force that inhibits change in the state of movement of a body when acted on by an applied force.

Answer 26

Reaction force

Question 27

is a force density. (i.e. N/m

Answer 27

Distributed force

Question 28

A sketch showing the physical conditions of the problem

Answer 28

Space Diagram:

Question 29

: A sketch showing only the forces on the selected particle

Answer 29

Free-Body Diagram

Question 30

forces are shown in a free-body diagram.

Answer 30

External

Question 31

Force Systems According to Line of Action

forces whose lines of action pass through a common point

Answer 31

Concurrent forces

Question 32

Force Systems According to Line of Action

forces whose lines of actions are parallel

Answer 32

Parallel forces

Question 33

Force Systems According to Line of Action

Non-concurrent forces

Answer 33

• forces whose lines of actions are neither parallel nor intersect in a common point

Question 34

the resultant force on a particle is zero, the particle will remain at rest or continue to move in a straight line

Answer 34

Newton’s First Law

Question 35

A particle will have an acceleration proportional to a nonzero resultant applied force.

F= ma

Answer 35

• Newton’s Second Law

Question 36

The forces of action and reaction between two particles have the same magnitude and line of action with opposite sense.

Answer 36

Newton’s Third Law:

Question 37

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

Moving the point of application of the force F to the rear bumper does not affect the motion or the other forces acting on the truck.

Answer 37

Principle of Transmissibility

Question 38

Problem Statement:

Free-Body Diagrams:

Fundamental Principles:

Solution Check:

Answer 38

Method of Problem Solution

Question 39

Includes given data, specification of what is to be determined, and a figure showing all quantities involved.

Answer 39

Problem Statement

Question 40

Create separate diagrams for each of the bodies involved with a clear indication of all forces acting on each body

Answer 40

Free-Body Diagrams

Question 41

Determine what theories are required for solution. Write down the equations to be used. Make substitutions into the equations only after you are confident that all of the correct equations have been selected.

Answer 41

Fundamental Principles:

Question 42

• Test for errors in reasoning by verifying that the units of the computed results are correct,
• test for errors in computation by substituting given data and computed results
• always apply experience and physical intuition to assess whether results seem “reasonable”

Answer 42

Solution Check: