GEN SCI ST2 MOVEMENT AND HUMAN MOVEMENT

Mechanics

The study of the motion of an object and the forces acting on it, which has two main branches: Kinematics and Dynamics.

Kinematics

The study of motion without considering the forces that cause it, focusing specifically on "how" an object moves.

Dynamics

The study of "why" motion occurs, focusing on forces and their effects on the motion and equilibrium of objects.

Motion

A change in position over time relative to a fixed point.

Reference Point

A place or object used for comparison to determine if something is in motion.

Relative Motion

The concept that an object can be in motion relative to one observer but at rest relative to another.

Vector Quantities

Quantities described by both magnitude and direction, such as velocity, force, and displacement.

Scalar Quantities

Quantities described by magnitude alone, such as speed, mass, and distance.

Translational Motion

Occurs when an object moves from one place to another where every part of the object moves in the same direction and covers the same distance.

Rectilinear Motion

A type of translational motion where an object moves in a perfectly straight line.

Curvilinear Motion

A type of translational motion where an object moves along a curved path without spinning.

Rotational Motion

The motion of a body about a fixed axis where every point on the body moves in a circular path and changes its orientation relative to its center.

Contact Forces

Forces that act between objects that are physically touching, such as tension, friction, and normal force.

Tension

A pulling force exerted through a rope, string, or wire.

Friction

A force that resists motion between surfaces that are in contact.

Normal Force

A support force exerted upon an object that is in contact with another stable object.

Non-Contact Forces

Forces that act over a distance without physical contact, such as gravity, magnetic force, and electric force.

Linear Displacement

The straight-line distance measured from an object's starting point to its ending point, measured in meters, kilometers, or miles.

Angular Displacement

The angle through which an object rotates around a fixed axis, measured in radians, degrees, or revolutions.

Linear Velocity

The rate at which an object changes its linear position over time, measured in meters per second or kilometers per hour.

Angular Velocity

The rate at which an object spins or changes its angle over time, measured in radians per second or revolutions per minute.

Linear Acceleration

The rate at which an object's forward linear velocity changes over time, measured in meters per second squared.

Angular Acceleration

The rate at which an object's spinning speed changes over time, measured in radians per second squared.

Force

A push or pull acting on an object that causes linear acceleration according to Newton's Second Law, measured in Newtons.

Torque

The rotational equivalent of force that acts as a twisting or turning effort depending on where force is applied relative to a pivot, measured in Newton-meters.

Inertia

An object's natural resistance to a change in its linear motion, measured simply by its mass in kilograms regardless of its shape.

Moment of Inertia

The resistance of a body to changes in its rotational speed, which depends on both mass and how that mass is distributed relative to the axis of rotation.

Biomechanics

The study of how mechanical quantities influence the movement of living organisms.

Sprint (Motion Type)

An example of translational motion because running covers a specific change of position over time.

Sprint (Kinematic Values)

An athletic movement resulting in an increase in linear velocity from a resting position with an angular velocity of zero.

Arm Rotations (Motion Type)

An example of rotational motion involving a complete 360-degree turning of the arms while the upper limb is extended.

Arm Rotations (Kinematic Values)

A movement following the concept of angular displacement where the ball-and-socket joint of the shoulder serves as the fixed axis.

Figure Skating Spin

A classic example of rotational motion where an athlete rotates around a vertical axis of the body.

Ice Spinner Friction

The reduction of resistance between the ice surface and skate blades allowing a skater to maintain rotational velocity.

Ice Spinner Centripetal Force

The inward pulling force keeping a skater intact in a circular path during a high-speed spin.

Ice Spinner Moment of Inertia

An effect where pulling the arms inward decreases the distribution of mass from the axis to increase spin speed.

Ice Spinner Conservation of Angular Momentum

The physical law dictating that spinning speed must increase when a skater pulls their limbs closer to their rotation axis.

Ergonomics

The scientific discipline concerned with the understanding of interactions among humans and other elements of a system to optimize well-being and performance.

Ergonomic Chair Lumbar Support

A design feature meant to preserve the natural curvature of the spine and prevent slouching.

Ergonomic Chair Adjustable Armrests

A design feature that minimizes tension in the shoulders and neck by supporting the weight of the limbs.

Ergonomic Chair Seat Height Alignment

A setting ensuring feet rest flat on the floor with knees at a 90-degree angle to promote healthy circulation.

Ergonomic Keyboard Curved Layout

A design that aligns keys with the natural angle of the wrists to drastically minimize the risk of strain injuries.

Ergonomic Keyboard Palm Rest

A padded surface supporting the hands during breaks to prevent repetitive strain injuries.

Choreographer Physics Log

A written document tracking timestamps where translational and rotational dance movements happen alongside brief descriptions of kinematic quantities.