biomechanical movement

Question 1

n

newtons first law of inertia

Answer 1

a force is required to change the state of motion

Question 2

what is inertia

Answer 2

the resistance an object has to a change in its state of motion
- if it is moving in one direction it will condtinue to do so at the same velocity until another force is exerted apon it
- bigger the mass, larger the inertia of a body or object- more force needed to change its state of motion

Question 3

example of newtons first law

Answer 3

in high jump, athlete runs horizontallly towards the bar and then changes their state of motion at take off when they travel vertically to try to clear the bar

• in a penality, the ball will remain on the spot unless it is kicked by the player

Question 4

newtons second law of acceleration

Answer 4

the magnitude (size) and direction of the force determines the magnitude and direction of the accelaration

Question 5

what does the second law mean

Answer 5

magnitude and direction of the force applied to a body determine the magnitude and direction and direction of the acceleration given to a body
- rate of acceleration is directional proportional to the force causing the change
FORCE = MASS x ACCELERATION (F = MA)

Question 6

example of newtons second law

Answer 6

to provide acceleration at the start of a sprint race, an athlete will have to apply a large force internally with their gluteals, quadriceps and gastrocnemius as they drive forward
- a tennis player will impart a large force on the ball so that it accelerates over the net in the direction in which the force has been applied
- when player kicks the ball during a game, the acceleration of the ball is proportional to the size of the force. the harder the ball is kicked the further and faster it will go in the direction in which the force has been applied

Question 7

newtons third law of motion

Answer 7

for every action there is an equal and opposite reaction

Question 8

what does newtons third law describe

Answer 8

when 2 bodies exert forces on one another. action and reaction are equal and opposite and always occur in pairs
action acts on one of the bodies and the reaction to this action acts on the other body

Question 9

what is ground reaction force (GRF)

Answer 9

the equal and opposite force exerted on a performer who applies a muscular force on the ground
individual standing on the ground exerts a contact force and at the same time an equal and opposite ground reaction force is exerted by the ground on the individual
example:
swimmer pushing backwards on the water with their hands and feet. at the same time, the water thrusts the swimmer forwards ( reaction)

Question 10

examples of newtons third law

Answer 10

when a footballer jumps up to win a header, a force is exerted on the ground in order to gain height. at the same time, the ground exerts an upward force ( equal and opposite reaction) upon the player