Biomechanics

Question 1

What is Linear Motion?

Answer 1

Movement along a straight or curved line, with no rotation. All body parts move in the same direction at the same speed. Also referred to as translation.

Question 2

Define Rectilinear Motion.

Answer 2

Linear movement in a straight line. Examples include the body during sprinting or a basketball chest pass.

Question 3

What is Curvilinear Motion?

Answer 3

Linear movement along a curved trajectory. Examples include the path of a ball in a netball shot or a long-distance ski jump.

Question 4

Explain Angular Motion.

Answer 4

All parts of a body move through a rotational pathway, through the same angle, in the same direction, and at the same time.

Question 5

What is General Motion?

Answer 5

A combination of linear and angular motion. Most human movement consists of general motion.

Question 6

Define Distance in the context of Linear Motion.

Answer 6

How far an object has traveled from its start to finish position, regardless of direction.

Question 7

What is Displacement?

Answer 7

The overall change in position of an object, measured in magnitude and direction.

Question 8

How is Speed calculated?

Answer 8

Speed = Distance / Time

Question 9

What is Instantaneous Speed?

Answer 9

Speed at a given point in time.

Question 10

Define Velocity.

Answer 10

Speed in a given direction. Calculated as displacement traveled divided by the time taken.

Question 11

What is Instantaneous Velocity?

Answer 11

Velocity at a given point in time.

Question 12

True or False: Speed and velocity are equal if movement occurs in a straight line and in the same direction.

Answer 12

True.

Question 13

What is Acceleration?

Answer 13

The rate at which the velocity of a body changes with respect to time.

Question 14

Define Positive Acceleration.

Answer 14

Velocity is increasing.

Question 15

What is Negative Acceleration (Retardation)?

Answer 15

Velocity is decreasing.

Question 16

What does Zero Acceleration indicate?

Answer 16

No change in velocity.

Question 17

Define Angular Distance.

Answer 17

The sum of all angles as a body moves from its start position to its end position.

Question 18

What is Angular Displacement?

Answer 18

The difference in the angle between the start and end position of the body.

Question 19

How is Angular Speed calculated?

Answer 19

Angular Speed = Angular Distance / Time

Question 20

Define Angular Velocity.

Answer 20

Calculated by dividing angular displacement by time.

Question 21

What is Force?

Answer 21

The product of mass and acceleration (F = MA). Any interaction (push or pull) that changes the motion of an object.

Question 22

List the uses of Force.

Answer 22

• Get objects moving
• Stop objects moving
• Change the direction of a moving object
• Change the speed of a moving object
• Balance another force to keep an object still

Question 23

Differentiate between Contact and Noncontact Forces.

Answer 23

• Contact Forces: Forces that act on objects in direct contact (e.g., frictional forces, ground reaction forces)
• Noncontact Forces: Forces that act without direct contact (e.g., Gravity)

Question 24

What is Newton’s 1st Law (Law of Inertia)?

Answer 24

A body continues in its state of rest or motion unless acted upon by a force.

Question 25

Explain Newton's 2nd Law (Law of Acceleration).

Answer 25

The acceleration of a body is proportional to the force applied and inversely proportional to the object's mass (F = MA).

Question 26

State Newton's 3rd Law.

Answer 26

For every action, there is an equal and opposite reaction.

Question 27

Define Momentum.

Answer 27

A measure of the amount of motion possessed by a moving body. It is the product of mass and velocity.

Question 28

How is Impulse defined?

Answer 28

The application of force over a period of time to change the momentum of an object.

Question 29

What are the components of a lever?

Answer 29

* Resistance (or weight/load to be moved) * Axis (or pivot point/fulcrum) * Force (application of force/effort)

Question 30

What is a Fulcrum/Axis?

Answer 30

The point around which the lever rotates.

Question 31

Define the Effort/Force Arm.

Answer 31

The distance between the fulcrum and the point at which the force is applied.

Question 32

What is a Resistance Arm?

Answer 32

The distance between the fulcrum and the center of the resistance.

Question 33

What is a First Class Lever?

Answer 33

The axis is located in the middle, with the force and resistance on either side. Can be either a speed or force multiplier.

Question 34

Define a Second Class Lever.

Answer 34

The axis is located at the end, with the resistance in the middle and force applied at the end. Functions as a force multiplier.

Question 35

What defines a Third Class Lever?

Answer 35

The axis is located at one end, with the application of force in the middle and resistance applied at the opposite end. Functions as a speed multiplier.

Question 36

What is a Projectile?

Answer 36

An object propelled into the air or water affected only by gravity and air resistance.

Question 37

What is the role of Air Resistance in projectile motion?

Answer 37

Affects horizontal velocity.

Question 38

Define Trajectory.

Answer 38

The path of a projectile.

Question 39

What factors determine the flight path of a projectile?

Answer 39

* Angle of release * Speed of release * Height of release

Question 40

What is Balance?

Answer 40

The ability to neutralize forces that disturb equilibrium.

Question 41

Differentiate between Static and Dynamic Balance.

Answer 41

* Static Balance: The ability to hold a stationary position * Dynamic Balance: The ability to hold a moving position

Question 42

What is the Center of Gravity (COG)?

Answer 42

The theoretical point in an object where all of the body's mass is equally distributed.

Question 43

Define Base of Support (BOS).

Answer 43

The area bound by the outermost regions of contact between a body and support surface.

Question 44

List the factors affecting Balance.

Answer 44

* Mass of the object * Size of the base of support (BOS) * Height of the center of gravity (COG) above the base of support * Position of the line of gravity (LOG) relative to the base of support