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Flashcards in Quiz 1 Deck (45)
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1
Q

What is the study of forces and their effects

A

Mechanics

2
Q

Mechanics that deals with geometry of the motion of objects, displacement, acceleration, velocity

A

Kinematic

3
Q

Study of relationships between force system acting on the body and changes it produces in body motion

A

Kinetics

4
Q

Uses principles of mechanics for solving problems related to structure and function

A

Biomechanics

5
Q

What are the three examples of Scalars

A

Distance
Speed
Mass

MAGNITUDE ONLY

6
Q

What are the 6 vectors

A
Displacement 
Velocity
Acceleration
Weight
Momentum
Force

MAGNITUDE AND DIRECTION

7
Q

What is speed

A

Distance/Time

Ignorant of direction

Scalar quantity

8
Q

What is velocity

A

Displacement/time

Direction aware

9
Q

What is acceleration

A

Change in Velocity/Time

Vector Quantity, so means it has direction associated with it

10
Q

What is mass

A

Amount of matter that is in the object

G or KG

Scalar quantity

11
Q

What is weight

A

measure in N

Is the force of gravity working up on the object

1 kilogram=10 newtons=2.2 pounds

12
Q

What is momentum

A

Mass*Velocity

P=m*v

Vector quantity

13
Q

What is force

A

Action of push or pull

Measure in newtons

Vector quantity

F=m*a

14
Q

What is the law of inertia

A

An object at rest stays at rest and an object in motion remains in motion unless acted upon by an outside force

15
Q

A system in ___________ is either at rest or moving with a constant velocity

A

Equilibrium

16
Q

Law of force and Acceleration

A

Newtons 2nd law

The acceleration of an object depends directly upon the net force acting upon the object, and inversely upon the mass of the object

The observed change in motion is called acceleration

17
Q

The law of action and reaction

A

Newtons 3rd law

For every action, there is an opposite and equal reaction

18
Q

What is normal stress

A

The intensity of force perpendicular to the surface on which it acts

19
Q

What is shear stress

A

The intensity of force parallel to the surface on which it acts

20
Q

What is static friction

A

Exists when two contacting surfaces are not currently sliding relative to each other but do posses the potential for movement

21
Q

This is the ratio required to initiate a sliding motion between two bodies

A

Coefficient of static friction

22
Q

What is kinetic friction

A

Friction in cases when the two surfaces are already sliding relative to each other

Aka= dynamic friction

23
Q

As soon as a applied parallel force exceeds the static friction force and the object begins to slide, friction force actually decreases

A

Coefficient of kinetic friction

24
Q

What is pressure

A

Is the magnitude of a applied force acting over a given area

p= F/A

Measured as Newtons/meter or pascals (PA)

25
Q

What is tensile strength

A

Max stretch a material can withstand without rupture of skin = 9.25 N/mm

26
Q

What is work

A

Is performed when an object is displaced by the application of a force

Force x Distance

Measure in joules

Can be positive or negative

27
Q

What is kinetic energy

A

The energy an object posses due to motion

Measure in joules

KE=1/2mv2

Changes in velocity have large effects on kinetic energy

28
Q

What is angular motion

A

The path of motion around a fixed axis and therefore in a circular path

29
Q

What is angular velocity

A

Time rate of change of angular position of a rotating body

Degrees or radians per unit of time

30
Q

What is angular acceleration

A

Time rate of change of angular velocity of a rotating body

31
Q

What is the axis of rotation

A

The point about which a body rotates

32
Q

What is the lever arm

A

Aka force arm, moment arm

Perpendicular distance from an axis of rotation to a line along which a force acts

33
Q

What is torque

A

Product of force and lever arm

34
Q

We move due to what force

A

Torque

35
Q

A _______________________ consists of a rigid or semi rigid object (lever) that is capable of rotating about an axis (fulcrum)

A

Lever system

36
Q

What is a type one lever

A

Fulcrum between the effort and load, ex. See saw

37
Q

What is a type 2 lever

A

Load is between the fulcrum and effort

Ex. Stapler, wheelbarrow

38
Q

What is a type 3 lever

A

Effort is between the fulcrum and the load’

Ex. Fishing rod, broom

39
Q

Example of type 1 lever in body

A

Neck

40
Q

Example of type 2 lever in body

A

Achilles and calcaneous

41
Q

Example of type 3 lever in body

A

Elbow joint

Most common

42
Q

> 1

A

Force advantage

43
Q

<1

A

Speed and range of motion

44
Q

What is mechanical advantage

A

Mm/Mr

45
Q

If the fulcrum is directly in the middle of the lever, the ratio is 1.00 which force has an advantage

A

Neither