問題一覧
1
What is an aerofoil?
an object that has a shape that creates lift in a moving fluid
2
What does "angle of incidence" mean?
the angle between the path of an object and a line drawn perpendicular from the surface with which it is presently in contact (i.e. the normal line)
3
What does "angle of reflection" mean?
the angle between the path of an object and a line drawn perpendicular from the surface with which it is presently in contact (i.e. the normal line)
4
What does "coefficient of drag" mean?
the numerical index of the resistance generated when a body moves through a fluid (values greater than 0)
5
what does "coefficient of friction" mean?
the numerical index of the liklihood that two surfaces in contact will not slide past each other (values greater than 0)
6
what does "coefficient of restitution" mean?
the numerical index of elasticity (energy retained) after a collusion of two bodies (values 0-1)
7
what does "coefficient of variation" mean?
the standard deviation (variability)of a series of measurements relative to the mean of the measurements
8
What does "braking Impulse" mean?
the product if the applied force and the time overwatch it is applied acting to slow an object (often occurs at foot striking in running)
9
What does "Impulse" mean?
the product of applied force and the time over which it is applied
10
What does "Impulse-momentum relationship" mean?
the relationship between impulse and momentum; the momentum of an object will change in proportion to the sum of applied impulses
11
What does "biomechanics" mean?
the field of science devoted to understanding mechanical principles in relation to biological organisms
12
What does "centre of bouyancy" mean?
the point about which the sum of bouyancy forces act (equivalent to the centre of gravity)
13
What does "form" mean?
the drag (profile / pressure drag) regarding resistance caused by a difference in pressure between the front and back of an object; proportional to the frontal surface area and shape (coefficient of drag) of an object and to the square of the velocity difference between the object and fluid
14
What does "heart rate reserve" mean?
the difference between resting and maximum heart rates
15
What does "inertia" mean?
the tendency of an object to remain in its constant state of motion
16
What does "external work" mean?
a force that is applied by a source external to the body (or system) causing a displacment of the body
17
What does "internal work" mean?
one part of a body or system applies a force on another part of the body, causing displacement
18
What does "kinematics" mean?
the description of how an object moves with respect to time; its pattern or sequencing of movement
19
What does "kinetic chain" mean?
the linked segments of a body that move together
20
What does "kinetic energy" mean?
the energy associated with motion; equal to the product of half an objects mass and the square of its velocity
21
What does "Magnus Effect" mean?
the changing of trajectory of an object towards the direction of spin; results from the Magnus force
22
What does "Magnus force" mean?
the lift force acting on a spinning object
23
What does "moment" mean?
pertaining to an action at a distance, for example, moment of inertia, moment of force
24
What does "moment arm" mean?
the perpendicular distance between a centre of rotation of an object and the line of action of a force acting on the object
25
What does "moment of inertia" mean?
tendency for a rotating body to remain in its present state of motion; equal to the product of the mass of an object and its radius of gyration
26
What does "moment of force (torque)" mean?
the result of a force acting at a distance from a centre of rotation; rotational action of a force
27
What does "normal reaction force" mean?
the force acting perpendicular to a surface
28
What does "parallax errror" mean?
the error of size or distance (and its time derivatives) associated with an objects movement across the field of view or that of the camera
29
What does "perspective errror" mean?
the error of size or distance (and its time derivatives) associated with an objects distance from the eyes or camera
30
What does "push-like movement pattern" mean?
the pattern of movement whereby the joints of linked segments extend (or flex) simultaeneously; optimum pattern for high forces and accuracy
31
What does "throw-like movement pattern" mean?
the pattern of movement whereby the joints of linked segments extend (or flex) in a sequential order, usually proximo-distally; optimum pattern for the attainment of high movement speeds
32
What does "realative velocity" mean?
the difference in velocities of two objects or media (for example, object and fluid)
33
What does "scaling factor" mean?
the relationship between arbitrary units and real-world units; arbitrary per real-world unit
34
What does "surface drag" mean?
(skin, friction, viscous drag) retarding resistance caused by a friction between an objects surface and a fluid moving relative to it
35
What does "translation" mean?
linear motion
36
What is a "vector"
a physical quantity described by both a magnitude and direction
37
What does "wave" mean?
a drag retarding resistance caused by pressure differences around an object moving at an interface between two liquids (for example, air and water) that results in wave formation in the more dense fluid
38
What does "work" mean?
the product of force and displacement; force provided over a range of object movement. It can be "internal" (produced by our own muscles) or "external" (the product of an external force)
39
What does "work-energy relationship" mean?
the change in energy of a body or system is directly proportional to the work done on the object or system; both work and energy have the same unit of measurement
40
What does "radian" mean?
a unit if angular fisplacement equal to the angle covered when a line joinginf the centre of a circle to the perimeter is rotated by the length of one radius