Gravitational Forces

Question 1

Newton’s First Law

Answer 1

(Law of Inertia) an object in motion tends to stay in motion & an object at rest tends to stay at rest unless acted upon by an outside force.

Question 2

Newton’s Second Law

Answer 2

Force = Mass x Acceleration

Question 3

Newton’s Third Law

Answer 3

For every action there is an equal and opposite reaction

Question 4

what is 1G (Gravity)

Answer 4

32.2 Ft/sec²

Question 5

What is Inertia

Answer 5

the resistance to a change in the state of rest or motion

Question 6

Acceleration

Answer 6

The (increased) rate of change of velocity with respect to time. Acceleration of gravity continues until terminal velocity is reached.

Question 7

Deceleration

Answer 7

A reduction in the velocity of a moving body with respect to time (negative acceleration)

Question 8

What is the Tri-axial Reference System

Answer 8

Identifies the direction in which the body receives accelerative forces. (X,Y, & Z axes)

Question 9

X-axis

Answer 9

the axis through the chest to back

Question 10

Y-axis

Answer 10

the axis across the shoulders

Question 11

Z-axis

Answer 11

the long axis along the spine from head to foot

Question 12

What are the factors of acceleration that affect severity of impact on the body

Answer 12

(BIRDI) Body Area and site Intensity Rate of onset Duration Impact direction

Question 13

How do changes in body surface area affect injury severity?

Answer 13

increase body surface area = decreased severity

Question 14

How do changes in intensity of acceleration forces effect injury severity?

Answer 14

increased intensity = increased severity

Question 15

How do changes in rate of onset of acceleration forces effect injury severity?

Answer 15

increased rate of onset = increased severity

Question 16

How do changes in duration of acceleration forces effect injury severity?

Answer 16

increased duration = increased severity

Question 17

How does impact direction effect injury severity?

Answer 17

all other factor being equal, y-axis impacts will result in more severe injury than z- or x-axis impacts. +Gx impacts are the most survivable.

Question 18

What are the factors that reduce the overall efficiency of the body to withstand G’s called?

Answer 18

Decremental factors

Question 19

What are the factors that enhance the ability of the body to withstand G-forces called?

Answer 19

Incremental factors

Question 20

Name some of the incremental and decremental factors with respect to +Gz

Answer 20

Decremental Factors: Dehydration, Alcohol Use, Blood Loss, Illness, Varicose Veins, Low Blood Pressure and Incremental Factors: Fear, Excitement, Asymptomatic Hypertension, G-suit, anti-G straining Maneuver

Question 21

Aircraft design features that enhance crash survivability (CREEP)

Answer 21

• Container
• Restraints
• Environment
• Energy absorption
• Post crash factors

Question 22

Occupant survivability during an accident sequence is contingent upon the what criteria?

Answer 22

The amount of crash forces transmitted and occupiable living space (Two objects cannot occupy the same space).

Question 23

________ is the resistance to a change in the state of rest or motion.

Answer 23

inertia

Question 24

________ is a reduction in the velocity of a moving body with respect to time.

Answer 24

deceleration

Question 25

The greater the ________ the more severe the effects of accelerative forces.

Answer 25

Intensity

Question 26

The longer a force is applied, the more severe the effect is, is the definition of ______.

Answer 26

duration

Question 27

Lateral accelerations in the G_____ axis are the most lethal to aircraft and occupants.

Answer 27

Y

Question 28

The _________ identifies the direction in which the body recieves accelerative forces.

Answer 28

tri-axial reference system

Question 29

The five physiological effects of high magnitude accelerations are?

Answer 29

• minor discomfort
• minor injury
• incapacitation
• irreversible injury
• lethal injury

Question 30

Aircrew members experience mild transverse accelerations during ______ and ______.

Answer 30

taking off, landing

Question 31

The primary source of high magnitude accelerations an deceleration are _________.

Answer 31

Aircraft crashes