Projectile Motion Flashcards
What is projectile motion?
The movement of a body through the air following a flight path under different forces acting
Give 3 examples of things that can have a projectile motion
> human bodies: flight phase of jumps
throwing implements: shot put, javelin, hammer
ball sports: tennis, golf
Which 3 forces act during flight and affect projectile motion?
- Gravity
- Air resistance
- Lift
How does gravity affect projectile motion?
> constantly pulls down on objects in flight
only forces it downwards when lift forces are weaker than gravitational pull
How does air resistance affect projectile motion?
> frictional forces occur when air passes over the surface of the object
faster object - greater air resistance
when air resistance is at its highest, it is called drag
shape and weight of an object influences air resistance
What is a parabola?
> the approximate have o the path of the object
U shaped curve
How does a shuttlecock’s parabola differ from a ‘true parabola’?
“Distorted parabola’
> when initially hit, high speed means large air resistance
> light weight causes it to slow down quickly
> air resistance rapidly decreases, causing shuttle to fall
What ar lift forces?
> forces causing an object to rise while in flight
How do lift forces work?
> discus is thrown
air flowing over he top has further to travel
therefore must travel quicker that air beneath
area of low pressure created on top
air travels slower under the discus
creating area of high pressure - pushing up causing it to rise
What is a parabolic flight path?
Flight with a uniform curve symmetrical about its highest point
> caused by the dominant force of weight on a projectile
> meaning air resistance is small
Give two examples of a parabolic flight path
> Shot or hammer throw
Human body in jumps and dives
What is a non-parabolic flight path?
A fight path asymmetrical about its highest point caused by the dominant force of air resistance on the projectile
> air resistance is dominant, weight is small
Give two examples of non-parabolic flight paths
> badminton shuttlecock
discus
What is horizontal displacement?
The distance a projectile has moved between its point of release and its point of landing, measured in a straight line parallel to the ground
What are 3 factors affecting horizontal displacement?
- Angle of release
- Speed of release
- Height of release
What is a projectile’s optimum angle of release dependant upon?
> optimal angle of release is dependant on release height and landing height
What is optimal angle of release when release height is below landing height?
> greater than 45 degrees
E.g. shooting in basketball
What is the optimal angle of release when the release height is greater than the landing height?
> lower than 45 degrees
E.g. a shot put, hand is higher than the ground
Describe the flight path of a projectile released at an angle of 90 degrees?
> projectile accelerates vertically upwards
comes straight back down
horizontal displacement of 0m
Describe the flight
> optimal angle to maximise horizontal distance
Describe the flight path of a projectile realeased at an angle of 60-75 degrees
> projectile reaches peak height too quickly
rapidly returns to the ground
Describe the flight path of a projectile with a release height of 30 degrees
> projectile does not achieve a sufficient height to maximise horizontal distance
How does speed of release affect a projectile’s horizontal displacement?
> greater velocity = greater displacement
due to Newton’s second law of acceleration
How does height of release affect horizontal displacement?
> greater height = greater displacement
reduces impact of gravity
How can technology be used to modify technique?
> analysis of footage (slowed down)
technique assessed
markers track motion
