LECTURE #7 - projectile motion Flashcards
what are the four important terms of projectile motion ?
- projectile
- trajectory
- release
- apex
what is trajectory ?
fight path of a projectile
what is projectile ?
object in free-fall that is affected only by gravity and air resistance
what is release ?
when object becomes a project (ex. angle of basketball being thrown)
what is apex ?
highest point in trajectory (highest point pleasing ball @ the apex)
how many primary purposes in projecting ?
5
what are the five primary purposes in projecting ?
- maximize horizontal distance
- maximize vertical height
- maximize accuracy
- maximize accuracy when speed enhances effectiveness
- maximize time in the air
what are examples of maximize horizontal distance ?
javelin, discus, shotput
what are examples of maximize vertical height ?
high jump, pole vault, etc.
what are examples of maximize accuracy ?
golf, basketball and archery
what are examples of maximize accuracy when speed enhances effectiveness ?
baseball throw, football toss, etc.
what are examples of maximize time in the air ?
gymnastics, diving, etc.
how many factors influencing projectile motion are there ?
3
what are the 3 factors influencing projectile motion ?
- relative height of release
- angle of release
- velocity of release
FILL IN THE BLANK
relative height of release = projectile _______
projectile height
FILL IN THE BLANK
angle of release = projection _____
projection angle
FILL IN THE BLANK
velocity of release = projectile ________
projectile velocity
TRUE OR FALSE
magnitude of the velocity = speed
TRUE
TRUE OR FALSE
more projectile height = more fight time
TRUE
given a constant projectile velocity & angle : increase or decrease for the following …
__ projectile height → __ flight time → __ horizontal displacement
↑ projectile height → ↑ flight time → ↑ horizontal displacement
TRUE OR FALSE (release Ht = landing Ht)
time to apex = time to land & v(y) release = v(y) landing
TRUE
TRUE OR FALSE (release Ht > landing Ht)
time to apex < time to land & v(y) release < v(y) landing
TRUE
TRUE OR FALSE (release Ht < landing Ht)
time to apex > time to land & v(y) release > v(y) landing
TRUE
what is projection angle ?
influences shape of projectile’s trajectory
describe the trajectory of projection θ = 90 degrees → ________ trajectory (v(x) = 0
vertical trajectory
describe the trajectory of projection θ = 0-90 degrees → ________ trajectory
parabolic trajectory
describe the trajectory of projection θ = 0 degrees → latter 1/2 _________ trajectory (v(y) initial = 0
parabolic trajectory
what two thing does optimal projection angle depend on ?
depends on goals of performance and projection height
define “depends on goals of performance”
maximize vertical displacement and maximize horizontal displacement
define “depends on projection height”
- release Ht = landing Ht
- release Ht > landing Ht
- release Ht < landing Ht
give an example of : release Ht = landing Ht
kick a ball for a max horizontal displacement
give an example of : release Ht > landing Ht
throw a ball for a max horizontal displacement
give an example of : release Ht < landing Ht
throw a ball onto elevated surface
what does projectile velocity determine (given a constant projectile angle & height) ?
projectile velocity determines magnitude of vertical and horizontal displacement
TRUE OR FALSE
velocity is a vector
TRUE
TRUE OR FALSE
velocity has a horizontal v(x) and vertical v(y) component ?
TRUE
TRUE OR FALSE
projectile have velocity ?
YES
describe vertical component v(y) :
- influences max vertical displacement
- constantly changing due to gravity
describe horizontal component v(x) :
- influences horizontal displacement (range)
- remains constant (assuming minimal air resistance)
TRUE OR FALSE
magnitude depends on projection angle
TRUE
TRUE OR FALSE
gravity is always pulling down ?
TRUE
do flat angles have smaller/larger horizontal/vertical component ?
flat angles have larger horizontal components
do steep angles have smaller/larger horizontal/vertical components ?
larger vertical component
between velocity, height and angle of release what is necessarily the most important ?
velocity (can continue to manipulate)