Chapter 3 - kinetic Concepts Of Human Movement

Question 1

What is Biomechanics

Answer 1

Study of living things from a mechanical perspective. The physics of human movement

Question 2

Kinetics

Answer 2

The study of forces that cause motion. (Torque, gravity, friction etc)

Question 3

Quantitative movement analysis

Answer 3

Looks at numerical data, (height, weight, mass, speed, distance, etc)

Question 4

Qualitative analysis

Answer 4

A description of the performance, (based on opinion)

Question 5

Force

Answer 5

A push or pull which alters that state of motion of a body

Force=mass x acceleration

Question 6

2 ways force affects an object

Answer 6

• Changes the shape of an object, (stretching, squashing or twisting)
• Moves the object, (speeds up or slows down, changes direction)

Question 7

Friction

Answer 7

• occurs when 2 surfaces come into contact with each other

- opposes the motion of an object and can be increased or decreased

Question 8

Drag (air and water resistance)

Answer 8

• when an object moves through air and water it experiences a drag force
• drag forces oppose the direction of motion of the object, slowing it down

Question 9

Gravitational force

Answer 9

On earth gravitational force is the force that causes objects to fall downwards towards the centre of the earth

Question 10

Mass

Answer 10

A measure of the amount of matter an object is made of

Question 11

Weight

Answer 11

• the force that is exerted on a body by gravity

Weight = mass x gravity

Question 12

Inertia

Answer 12

Objects at rest or in motion will continue to be in the same state unless acted upon by an external force

Eg, the greater the weight of an object, the greater the inertia

Question 13

Momentum

Answer 13

The measure of the amount of motion a body or object has

Momentum = mass (Kg) x velocity (m/s)

Question 14

Conservation of momentum

Answer 14

The total momentum of the body before the collision is equal to the total momentum after the collision

Question 15

Summation of momentum

Answer 15

The transfer of momentum from the larger, slower moving part to the smaller, faster moving parts to maximise the release of an object

Question 16

Impulse

Answer 16

Is equal to the change in momentum of an object. To change the momentum of an object, a force must be applied over a period of time

• impulse = force x time

Question 17

Newton’s first law of motion

Answer 17

An object not change its motion unless acted upon by an external force

Question 18

Newton’s second law of motion

Answer 18

A force applied to an object will produce a proportional acceleration to the size of the force it was acted upon

Question 19

Newton’s 3rd law of motion

Answer 19

For every action there is an equal and opposite reaction

Question 20

Newton’s first law of angular motion

Answer 20

The angular momentum of a body remains the same unless acted upon by an external torque

Question 21

Second law of angular motion

Answer 21

A torque applied to an object will produce a proportional acceleration to the size of the torque it was acted upon

Question 22

3rd law of angular motion

Answer 22

For every torque there is an equal and opposite torque

Question 23

What is a torque

Answer 23

A measure of how much a force acts in an object causing that object to rotate

Question 24

Angular motion

Answer 24

The product of the moment of inertia and angular velocity rotating a rounding an axis

Angular momentum = moment of inertia x angular velocity

Question 25

Moment of inertia

Answer 25

The resistance of an object to changes in angular momentum