Biomechanics- Projectile motion Flashcards
(7 cards)
Height of release and speed of release are two factors affecting the horizontal displacement of a projectile.
Name one other factor which affects the horizontal displacement of a projectile.
Angle of release (1)
A named force (air resistance/weight) (1)
The figure below shows the flight path of a shot put.
Sketch the vector components at the three points shown on the figure below, which represent:
* the point of release
* the highest point of flight
* the point immediately before landing.
[total 3 marks]
Horizontal component
* Horizontal component equal at each point (1)
Vertical component (submax 2)
* (the point of release) Positive vertical component. (1)
* (the highest point of flight) No vertical component. (1)
* (the point immediately before landing) Negative vertical component. (1)
All vectors must be drawn from the correct starting points.
The figure below shows the flight path of a shot put.
Analyse the factors affecting the flight path of the shot put and how an athlete can maximise horizontal displacement.
(Total 15 marks)
AO1 – Knowledge of the factors affecting horizontal displacement and the factors affecting flight paths
*Knowledge of horizontal displacement
*
* Horizontal displacement is the shortest distance from starting point to finishing point
* Factors affecting horizontal displacement are angle of release, speed of release and height of release
* This optimum angle of release is dependent on the release height of an object and landing height
* If the release height is greater than the landing height, the optimum angle of release needs to be less than 45° / If the release height is the same as the landing height optimum angle of release is 45° / If the release height is less than landing height the angle of release needs to be greater than 45°
* The greater the release velocity and release height of a projectile, the greater the horizontal displacement travelled
Knowledge of Flight Paths
* Weight and air resistance affect the flight paths of projectiles
* Projectiles with a large weight force tend to have a small air resistance force and follow a true parabolic flight path
* Parabolic flight path – flight path of a projectile in the absence of air resistance
AO2 – Application of knowledge to the shot put
* The shot put flight path is parabolic / symmetrical because air resistance is negligible
* Flight path is parabolic due to interaction between horizontal and vertical vectors and these change during the flight path
* The release height for the shot put is greater than the landing height (ground)
* The speed of release will also affect the distance travelled by the shot putt which relates to the speed of the spin / shuffle in the throwing circle
* This suggests an angle of less than 45° would be suitable for the shot put
AO3 – Analysis of the factors affecting the flight path of the shot put and how an athlete can maximise horizontal displacement
* The faster the speed of the shift / greater impulse / spin in the throwing circle the greater the velocity so a longer throw / horizontal displacement can be achieved. Having a high amount of fast twitch glycolytic fibres (2x) will aid with this
* Greater force on the shot put results in greater acceleration and therefore horizontal displacement
* The shot put has a parabolic flight path because it has a large weight force with little air resistance due to the relatively short time it is in the air
* As the shot put has a high mass the force of gravity is constantly acting on the mass of a shot put
* This therefore means that technically the shot putter should try to release the shot at the highest point possible above the ground to gain maximum horizontal displacement
* Keeping the release angle smaller means more speed can be generated as the shot is released
* The optimum angle of release for a shot putter will also depend on the size, strength and throwing technique of the athlete
* This also implies that taller shot putter will throw further if angle of release and velocity is the same which isn’t always the case either
Accept any other appropriate analysis of the flight path of the shot put and how an athlete can maximise horizontal displacement
The diagram below shows the forces affecting a shot put during flight.
Identify forces X and Y in the diagram.
[total 1 mark]
A
X: air resistance
Y: weight
B
X: friction
Y: gravity
C
X: weight
Y: air resistance
C
One event in the heptathlon is the shot put. This involves one powerful, explosive movement.
Name three factors that affect the distance the shot travels.
[total 1 mark]
Height, Speed and Angle of release
All 3 must be named correctly
Accept velocity for speed
The figure below shows the flight path of a shot.
Copy the figure and label your diagram to show the changing vertical and horizontal vectors at the following points:
- the point of release
- the highest point of flight
- the point immediately before landing.
Point of release
Positive vertical component
Arrows only required on diagram
Highest point
No vertical component
Specific points of flight path do not need to be identified
Before landing
Negative vertical component
Equal horizontal component at all three points in flight
Vector arrows must be present and attached to the correct point on the parabolic curve
In a game of badminton the performer hits the shuttle into the air and it then becomes a projectile. Explain how the various forces act to affect the badminton shuttle during its flight.
[total 3 marks]
The badminton shuttle follows a non parabolic flight path
The shape of the shuttle means air resistance is the larger force
Air resistance acts on the horizontal components
Gravity acts on the vertical components
Light object so the effect of weight is minimal
