biomechanics questions Flashcards
outline three ways in which newtons second law of motion would assist to kick the ball for distance
increase the speed of the kicking leg
increase run up speed
increase contact time of the foot on the ball
increase force by using segmental interaction
apply a follow through when kicking the ball to prevent deceleration
what are most of levers in the body
The majority of levers in the human body are third-class levers ie fulcrum at one end, force /effort in the middle and resistance at the opposite end
what happens if resistence arm is longer
When the resistance arm is longer than the force arm the speed of movement is increased
examples of levers
Sporting example
Using longer striking implements eg bats, racquets
Adjusting grip to lengthen lever eg holding cricket bat at the end
how does moment of inertia relate to a softballer hitting for maximal distance
reducing an object’s moment of inertia, one can increase the angular velocity of the object as it becomes easier to move
At the commencement of the swing, the softballer flexes at the elbows which brings the mass of the bat close to the axis of rotation to generate maximum velocity (make it easier to swing)
what type of lever is swinging a bat
3rd
how can you increase the distance a ball travels in relation to levers
3rd class lever wants to maximise the length of the resistance arm as velocity is greatest at the distal end
Just prior to contact, the softballer would extend her arms to maximise the length of the lever and therefore hit the ball harder
what is the resistance arm
the distance from the fulcrum to the location where the object you’re trying to move is positioned.
what is the force arm
the distance from the fulcrum to the location where you apply the force to move the load.
describe the direction of force applied in relation to the force motion principle
push is the direction of target to increase transfer of momentum through the ball
the ball effectively tracks on the stick in the direction of the desired target for an extended period of time
tackler can increase the impulse by increasing the force applied by either
increasing velocity of incoming tackler
increase strength/mass by going to gym
incorporate segmental interaction to produce greater force
describe how the angle of 5,85 and 45 will affect lift and drag
If the angle of the discus is too flat (50) to the oncoming resistance, then drag will be minimised (1 mark) however, there will be no lift created, and subsequently, the total distance will be low (1 mark)
If the angle of the discus is too great (850), then lift will be high (1 mark); however, drag will also be high due to the increased cross-sectional area presented to the oncoming air, reducing overall distance (1 mark)
If the angle of the discus is optimal (450), then the right balance between lift being maximised (1 mark) whilst drag is minimised is attained, allowing for maximal distance to be achieved.(1 mark)
what is surface drag
the drag created due to a fluid moving over an object resulting in friction between the surface of the body and the fluid.
what happens if the force arm is longer
This means that a relatively smaller force applied over a longer distance at the effort arm can overcome a larger resistance or load at the resistance arm, allowing you to generate more torque or rotational force.
what is class 2 lever good at
good at producing force: large resistence can be moved by a relatively small force
not good for producing speed
