Quiz #6 Flashcards
Motion of bodies that have been projected into the air
Projectile motion
Understanding _ _ helps in learning to control or predict what happens to an object when in the air
projectile motion
Solid line arcs up and drops below dotted line
Vertical displacement
Solid line goes diagonally down below dotted line
Vertical velocity
Solid line is below dotted line and is parallel
Vertical acceleration
- inanimate
- animate
classes of projectiles
- trajectory (parabola)
- instant of release
- instant of contact
projectile motion definitions
Factors that influence the trajectory of a projectile
- projection angle
- projection speed
- projection height
Factors that influence the trajectory of a projectile: projection angle
- 0 degrees indicates a directly _ _
horizontal projection
Factors that influence the trajectory of a projectile: projection angle
- 90 degrees indicates a directly _ _
vertical projection
Factors that influence the trajectory of a projectile: Projection angle
- Between 0 and 90 degrees trajectory will be _
parabolic
Factors that influence the trajectory of a projectile: projection speed
Strongly influences the _ and _ of trajectory
height, length
Factors that influence the trajectory of a projectile: projection speed
- _ _of release (takeoff) determines:
- height achieved after release
- time it takes to reach maximum height
- time it takes to fall back to the release position
- the velocity of the object when it returns to release position
vertical speed
Factors that influence the trajectory of a projectile: projection speed
- _ _of release (takeoff)
- in the absence of air resistance remains constant until the instant of contact
- along with the time in the air determines horizontal distance (range)
- becomes smaller as the projection angle approaches 90 degrees
- becomes larger as the projection angle approaches 0 degrees
horizontal speed
Factors that influence the trajectory of a projectile: projection height
- difference in vertical height between the instant of release and the instant of contact
- height at instant of release _ height at instant of contact (soccer kick)
=
Factors that influence the trajectory of a projectile: projection height
- difference in vertical height between the instant of release and the instant of contact
- height at instant of release _ height at instant of contact (shot put)
>
Factors that influence the trajectory of a projectile: projection height
- difference in vertical height between the instant of release and the instant of contact
- height at instant of release _ height at instant of contact (free throw)
<
Projection height - release height = contact height (soccer kick)
- Distance up _ distance down
- Vertical speed at the instant of release _ vertical speed at the instant of contact
- to maximize range projection angle _ 45 degrees
- =
- =
- =
Projection height - release height = contact height (soccer kick)
- parabola is _
- time up _ time down
- Horizontal distance while object goes up _ horizontal distance while object goes down
- symmetric
- =
- =
Projection height - release height > contact height (shot put)
- parabola is _
- time up _ time down
- Horizontal distance while object goes up _ horizontal distance while object goes down
- asymmetric
- <
- <
Projection height - release height > contact height (shot put)
- Distance up _ distance down
- Vertical speed at the instant of release _ vertical speed at the instant of contact
- to maximize range projection angle _ 45 degrees
- <
- <
- <
Projection height - release height < contact height (Free throw)
- Distance up _ distance down
- Vertical speed at the instant of release _ vertical speed at the instant of contact
- to maximize range projection angle _ 45 degrees
- >
- >
- >
Projection height - release height < contact height (Free throw)
- parabola is _
- time up _ time down
- Horizontal distance while object goes up _ horizontal distance while object goes down
- asymmetric
- >
- >
(Vf)^2 = Vi^2 + 2a(Pf - Pi)
equation of motion
(Yvf)^2 = Vvi^2 + 2a(Yf - Yi)
vertical motion
(Vhf)^2 = Vhi^2
horizontal motion
The description of angular motion without regard to its cause
angular kinematics
All parts on the object of interest move through the same angle, but do not undergo the same linear displacement
angular
Two lines that intersect at a vertex
- vertex (axis, joint)
angle
Types of angular motion in human movement:
- the knee
about an axis through a joint
Types of angular motion in human movement:
- somersault or twist
about the center of mass
Types of angular motion in human movement:
- high bar in gymnastics
about an external axis
Types of angular motion in human movement:
- each assumes that the axis is _
- often only have an instantaneous _ _ _
- stationary
- center of rotation
Angular kinematics: units of measurements
- revolution
- degree
- radian
Angular kinematics: units of measurements
- layman description of halves and wholes
- implied
- full twisting, double back somersault
revolution (rev)
Angular kinematics: units of measurements
- more scientific but not mathematical
- normally used to describe part of a revolution
Degree (deg)
Angular kinematics: units of measurements
1 deg = _ of a revolution
1/360
Angular kinematics: units of measurements
- the measure of an angle from a circle’s center described by an arc equal to the length of the radius of the circle
- scientific and mathematical
- unit is dimensionless
radian (rad)
Angular kinematics
- types of angles
- absolute angles (segment angles)
- relative angles (joint angles)
Angular kinematics: Types of angles
- describes the orientation of a segment in space
absolute angle
Angular kinematics: Types of angles
- describes the orientation of a joint in space
relative angle
