1. Biomechanics

2.  The study of forces and their effects on the human body

3.  Sir Isaac Newton developed three basic laws that explain the relationship between motion and force

4.  A push, a pull or a twist  Force = Mass x Acceleration

5.  LAW OF INERTIA  “A body continues in its state of rest or uniform motion unless an unbalanced force acts upon it“  So what does this mean?  A body will remain at rest or will continue moving (in the same direction) until another force acts on it

6.  Inertia is…  a body’s tendency to remain at rest or in motion. The more mass an object has, the larger its inertia is. Therefore is more reluctant to change its state of motion.  Who has more inertia in this image?

7.  This soccer ball will remain at rest until a force acts on it…  e.g. strong winds, or someone kicking it

8.  LAW OF ACCELERATION  ‘The acceleration of an object is directly proportional to the force causing it, is in the same direction as the force, and is inversely proportional to the mass of the object’  This means…  When a force is applied to an object it will move in the direction the force was applied, and, depending on the size of the force and the size of the object, the object will accelerate accordingly  Class experiment…

9.  A smaller object will move faster than a larger object.  A greater force will move an object faster than a smaller force Force = Mass x acceleration

10.  THE LAW OF REACTION  ‘Whenever a force is applied there is an equal and opposite reaction’  e.g. Jumping  If a person exerts a force onto the ground in order to push off, the ground will exert an equal and opposite force on the person, pushing them up into the air Upward Downward

11.  HANDBALL EXAMPLE  In your groups, choose ONE of Newton’s Laws  Describe how you can use this law to your advantage in Handball

12.  Levers allow you to apply force and speed more easily.  Consist of 5 parts - Fulcrum (pivot point), Force, Force arm, Resistance and a Resistance Arm FORCE ARM Resistance Fulcrum FORCE Resistance ARM

13.  Allow force to be applied from Outside the body  e.g.

14.  Are inside the human body.  Most important Levers  These levers are made up of a:  Joint = Fulcrum  Bones = Lever arms  Muscles = Force  Load = resistance  Effort = force

15.  Levers can be classed into 3 types:  1 st Class  2 nd Class  3 rd Class – Most levers in human body are 3 rd class

16.  In a 1 st Class Lever, the Fulcrum sits between the load (resistance) and force applied (effort)  e.g. See-saw

17.  In a 2 nd Class Lever, the Load (resistance) sits between the fulcrum and the force applied.  e.g. Wheel Barrow

18.  In a 3 rd class lever, the force applied sits between the Fulcrum and the load (resistance)  Third class levers allow more speed to be produced because resistance arm is longer than force arm  e.g. Bicep curl

19.  To Manipulate the Lever length the resistance arm needs to be altered (via bending or straightening the joint)  Longer levers result in greater speed at the end of the lever arms – this is beneficial for throwing and striking objects (e.g. throwing a handball).  Short levers result in fast and strong movements to occur– this is beneficial for moving body parts quickly and applying strength for pushing, pulling and lifting objects.

20.  1. What class of lever are most of the limbs in human body?  2. Force = _______ x ________  3. Newton’s 1 st law is the law of _______  4. Newton’s 2 nd law of reaction means… ?  5. What type of joint is the elbow joint? And what muscle causes elbow flexion

21.  1. What class of lever are most of the limbs in human body? 3 rd CLASS  2. Force = MASS x ACCELERATION  3. Newton’s 1 st law is the law of INERTIA  4. Give an example of Newton’s 2 nd law?  BOUNCING A BALL, JUMPING  5. What type of joint is the elbow joint? And what muscle causes elbow flexion  HINGE JOINT, BICEP

22.  ‘the sum of all forces generated by each body part’  Force summation allows maximum force to be produced  For maximum force production: 1. The force from all different body segments needs to be added together 2. Use large muscles  then smaller muscles 3. You need to sequence timing of body segments 4. The more body segments that are involved in the movement, the more possible force that can be produced

23.  Throwing example: Time Force Produced Large Force Small Force Shoulder/arm Hand Trunk Hip/thigh/leg

25.  As soon as an object is thrown it becomes a projectile.  The distance an object travels is dependant on many factors, including:  Speed of release  Angle of release  Height of release

26.  A projectiles speed of release is determined by:  Force summation  Levers  The greater the speed of release = the greater distance traveled.

27.  When aiming for maximum distance, the optimal angle of release is 45 degrees  Different activities require a different angle of release…  e.g. Hand ball shot at goal (-45 degrees)  e.g. Throwing a shot put (45 degrees)  – High release to get greater distance

28.  By increasing the height of release, the object will travel a greater distance  e.g.

29.  Complete the revision worksheet