unit 1 – area of study 2 biomechanical movement principles
DESCRIPTION
UNIT 1 – area of study 2 Biomechanical movement principles. PROJECTILE MOTION. What does this picture mean to you?. PROJECTILE MOTION. # Projectile motion is very common in sporting situations. # Once a person or object becomes airborne it becomes a projectile. # Examples : - PowerPoint PPT PresentationTRANSCRIPT
UNIT 1 – AREA OF STUDY 2BIOMECHANICAL MOVEMENT
PRINCIPLES
PROJECTILE MOTION
What does this picture mean to you?
PROJECTILE MOTION# Projectile motion is very
common in sporting situations.
# Once a person or object becomes airborne it becomes a projectile.
# Examples :ball sports ( tennis / volleyball )gymnastics ( vault / floor )athletics ( javelin / high jump )
FACTORS AFFECTING PROJECTILES FACTORS THAT CANNOT BE CONTROLLED
BY THE PERFORMER :* GRAVITY* AIR RESISTANCE
FACTORS THAT CAN BE CONTROLLED BY THE PERFORMER :
* VELOCITY OF RELEASE* ANGLE OF RELEASE* HEIGHT OF RELEASE* SPIN
FACTORS AFFECTING PROJECTILES GRAVITY
Gravity is a constant force that pulls projectiles down towards earth.
It is gravity that creates a projectile’s PARABOLIC fight path.
-------- PARABOLA
FACTORS AFFECTING PROJECTILES AIR RESISTANCE
Air resistance acts in the opposite direction to a projectile’s flight and slows its horizontal velocity.
Therefore air resistance reduces the horizontal distance a projectile will travel.
-----------NO AIR RESISTANCE
AIR RESISTANCE--------
FACTORS AFFECTING PROJECTILES VELOCITY OF RELEASE
Velocity of release is the most important factor when trying to maximise the horizontal distance a projectile will travel.
The greater the force applied, the greater will be the velocity at release and the further the projectile will go.
FACTORS AFFECTING PROJECTILES VELOCITY OF RELEASE
Velocity of release is the most important factor when trying to maximise the horizontal distance a projectile will travel.
The greater the force applied, the greater will be the velocity at release and the further the projectile will go.
SLOW RELEASE--------
FACTORS AFFECTING PROJECTILES VELOCITY OF RELEASE
Velocity of release is the most important factor when trying to maximise the horizontal distance a projectile will travel.
The greater the force applied, the greater will be the velocity at release and the further the projectile will go.
FASTER RELEASE--------SLOW RELEASE--------
FACTORS AFFECTING PROJECTILES VELOCITY OF RELEASE
Velocity of release is the most important factor when trying to maximise the horizontal distance a projectile will travel.
The greater the force applied, the greater will be the velocity at release and the further the projectile will go.
FASTER RELEASE--------SLOW RELEASE--------
--------FASTEST RELEASE
FACTORS AFFECTING PROJECTILES ANGLE OF RELEASE
The angle of release is the angle the object is projected into the air and will depend on the sport.* volleyball block = straight up* high jump = relatively high projection* tennis forehand = relatively flat projection* lawn bowls = straight out
Where the release and landing points are at the same level the best angle for maximum horizontal distance is 45 degrees.
This gives the best combination of vertical velocity to give optimal flight time and horizontal velocity to give distance.
FACTORS AFFECTING PROJECTILES ANGLE OF RELEASE
60 DEGREES--------30 DEGREES--------
--------45 DEGREES
FACTORS AFFECTING PROJECTILES HEIGHT OF RELEASE When the height of release is the same as the landing height then the
best angle of release is 45 degrees.
When the point of release is higher than the landing point ( ie: shot put ) the optimal angle of release will be less than 45 degrees.
When the velocity of release and the angle of release remain constant, a projectile released from higher will travel further as it has a longer flight time.
FACTORS AFFECTING PROJECTILES HEIGHT OF RELEASE When the height of release is the same as the landing height then the
best angle of release is 45 degrees.
When the point of release is higher than the landing point ( ie: shot put ) the optimal angle of release will be less than 45 degrees.
When the velocity of release and the angle of release remain constant, a projectile released from higher will travel further as it has a longer flight time.
LOW RELEASE--------
FACTORS AFFECTING PROJECTILES HEIGHT OF RELEASE When the height of release is the same as the landing height then the best
angle of release ( for max horizontal distance ) is 45 degrees.
When the point of release is higher than the landing point ( ie: shot put ) the optimal angle of release will be less than 45 degrees.
When the velocity of release and the angle of release remain constant, a projectile released from higher will travel further as it has a longer flight time.
LOW RELEASE--------
HIGH RELEASE-------
FACTORS AFFECTING PROJECTILES SPIN THE MAGNUS EFFECT :
When a ball travelling through the air is also spinning, one half of the ball spins in opposition to the oncoming air whilst the other half of the ball spins in the same direction as the oncoming air.
FACTORS AFFECTING PROJECTILES SPIN THE MAGNUS EFFECT :
When a ball travelling through the air is also spinning, one half of the ball spins in opposition to the oncoming air whilst the other half of the ball spins in the same direction as the oncoming air.
SPIN
ONCOMING AIR
FACTORS AFFECTING PROJECTILES SPIN THE MAGNUS EFFECT :
When a ball travelling through the air is also spinning, one half of the ball spins in opposition to the oncoming air whilst the other half of the ball spins in the same direction as the oncoming air.
SPIN
ONCOMING AIR
AIR FLOWWITH THE SPIN
FACTORS AFFECTING PROJECTILES SPIN THE MAGNUS EFFECT :
When a ball travelling through the air is also spinning, one half of the ball spins in opposition to the oncoming air whilst the other half of the ball spins in the same direction as the oncoming air.
SPIN
ONCOMING AIR
AIR FLOWWITH THE SPIN
AIR FLOWAGAINSTTHE SPIN
FACTORS AFFECTING PROJECTILES SPIN THE MAGNUS EFFECT :
When a ball travelling through the air is also spinning, one half of the ball spins in opposition to the oncoming air whilst the other half of the ball spins in the same direction as the oncoming air.
Different air flow creates a pressure difference with the ball moving from HIGH to LOW pressure.
SPIN
ONCOMING AIR
AIR FLOWWITH THE SPIN
AIR FLOWAGAINSTTHE SPIN
FACTORS AFFECTING PROJECTILES SPIN THE MAGNUS EFFECT :
When a ball travelling through the air is also spinning, one half of the ball spins in opposition to the oncoming air whilst the other half of the ball spins in the same direction as the oncoming air.
Different air flow creates a pressure difference with the ball moving from HIGH to LOW pressure.
SPIN
ONCOMING AIR
AIR FLOWWITH THE SPIN
AIR FLOWAGAINSTTHE SPIN
HIGH LOW
FACTORS AFFECTING PROJECTILES SPIN THE MAGNUS EFFECT :
When a ball travelling through the air is also spinning, one half of the ball spins in opposition to the oncoming air whilst the other half of the ball spins in the same direction as the oncoming air.
Different air flow creates a pressure difference with the ball moving from HIGH to LOW pressure.
SPIN
AIR FLOWWITH THE SPIN
AIR FLOWAGAINSTTHE SPIN
HIGH LOW
BALL CURVES
FACTORS AFFECTING PROJECTILES TOPSPIN
SPIN
FACTORS AFFECTING PROJECTILES TOPSPIN
SPIN
HIGH
LOW
A HIGH pressure on the top of the ball and a LOW pressure on the bottom of the ball causes it to “DIP” in the air.
FACTORS AFFECTING PROJECTILES TOPSPIN
SPIN
HIGH
LOWBALL DIPS
A HIGH pressure on the top of the ball and a LOW pressure on the bottom of the ball causes it to “DIP” in the air.
FACTORS AFFECTING PROJECTILES BACKSPIN
SPIN
FACTORS AFFECTING PROJECTILES BACKSPIN
SPIN
HIGH
LOW
A HIGH pressure on the bottom of the ball and a LOW pressure on the top of the ball causes it to “HANG” in the air.
FACTORS AFFECTING PROJECTILES BACKSPIN
SPIN
HIGH
LOW
BALL HANGS
A HIGH pressure on the bottom of the ball and a LOW pressure on the top of the ball causes it to “HANG” in the air.
FACTORS AFFECTING PROJECTILES SIDESPIN
SPIN
FACTORS AFFECTING PROJECTILES SIDESPIN
SPINHIGH LOW
A HIGH pressure on one side of the ball and a LOW pressure on the other side of the ball causes it to “CURVE” in the direction of the spin.
FACTORS AFFECTING PROJECTILES SIDESPIN
SPINHIGH LOW
BALL CURVES
A HIGH pressure on one side of the ball and a LOW pressure on the other side of the ball causes it to “CURVE” in the direction of the spin.
FACTORS AFFECTING PROJECTILES EFFECT OF SPIN ON REBOUND * TOPSPIN
SPIN
FACTORS AFFECTING PROJECTILES EFFECT OF SPIN ON REBOUND * TOPSPIN
SPIN
LOW & FAST
The ball is spinning in the same direction as its travel so friction is reduced and the ball bounces “LOW” & “FAST”.
FACTORS AFFECTING PROJECTILES EFFECT OF SPIN ON REBOUND * BACKSPIN
SPIN
FACTORS AFFECTING PROJECTILES EFFECT OF SPIN ON REBOUND * BACKSPIN
SPIN
SLOW & HIGH
The ball is spinning in the opposite direction as its travel so friction is increased and the ball bounces “SLOW” & “HIGH”.
FACTORS AFFECTING PROJECTILES
SPIN
EFFECT OF SPIN ON REBOUND * SIDESPIN
FACTORS AFFECTING PROJECTILES
SPIN
Friction created by the ball’s spin causes it to bounce in the direction of the spin.
EFFECT OF SPIN ON REBOUND * SIDESPIN
REVISION QUESTIONS1. The horizontal distance a projectile travels depends on :
A/ velocity at release.B/ angle of release.C/ height of release.D/ all of the above.E/ none of the above.
2. When throwing a discus for distance, providing that all else remains constant, a taller person will:
A/ throw at the same angle.B/ throw at an increased angle.C/ throw at a decreased angle.D/ throw at 45 degrees.
3. When the height of release is the same as the height of the landing, the bestangle of release for maximum horizontal distance is :
A/ 30 degrees.B/ 45 degrees.C/ 60 degrees.D/ 90 degrees.
REVISION QUESTIONS4. Explain the "MAGNUS EFFECT" as it relates to a spinning ball.
When a ball traveling through the air is also spinning – one half of the ball spins in opposition to the oncoming air whilst the other half of the ball spins in the same direction as the oncoming air. This creates a pressure difference on the two sides of the ball with the ball always moving or curving from high pressure to low pressure zones.5. State the effect of the following spins on the flight of a ball.
(a)Topspin : (b) Backspin :
(c) Sidespin :
The ball dips down in the air
The ball hangs up in the air
The ball curves to the side
5. State the effect of the following spins on the bounce of a ball.(a)Topspin : (b) Backspin :
(c) Sidespin :
The ball bounces low and fast
The ball bounces high and slow
The ball bounces to the side