Science 9 Review: Concepts of Motion and Energy

Flashcards covering key concepts regarding motion, energy, and thermodynamics from a Science 9 lecture.

Uniformly Accelerated Motion (UAM)

Refers to an object with constant acceleration where the speed/velocity changes at a constant rate in a given time interval.

Freefall Motion

The motion of a falling object under the influence of gravity alone, with air resistance considered negligible.

Acceleration due to gravity (g)

The constant acceleration involved in freefall, equal to -9.8 m/s², indicating its downward direction.

Projectile Motion

The motion of an object projected into the air at an angle less than 90 degrees, characterized by a constant horizontal velocity and zero vertical velocity at maximum height.

Maximum range of a projectile

Achieved when a projectile is fired at an angle of 45 degrees with respect to the horizontal.

Momentum

Defined as inertia in motion or the product of mass (m) and velocity (v), represented by the formula p = mv.

Impulse

The change in momentum that results from applying a force over a period of time.

Collision

Occurs when two or more objects come into contact, leading to a transfer of momentum and kinetic energy.

Elastic Collision

A collision in which total kinetic energy does not change and colliding objects bounce off without deformation.

Inelastic Collision

A collision in which total kinetic energy changes, objects stick together after collision, and there is deformation.

Conservation of Momentum

States that total momentum before a collision equals total momentum after a collision.

Energy

The ability to do work, measured in Joules (J).

Potential Energy

Energy possessed by an object at rest, stored for later use.

Kinetic Energy

Energy possessed by an object in motion.

Law of Conservation of Energy

Energy cannot be created or destroyed, only transformed from one form to another.

Thermodynamics

The science that describes how thermal energy is converted and how it affects matter.

Heat

The thermal energy that flows from a substance of higher temperature to one of lower temperature.

Open System

A system that can exchange both energy and matter with its surroundings.

Closed System

A system that can exchange only energy, not matter, with its surroundings.

Isolated System

A system that cannot exchange matter or energy with its surroundings.

Heat Engine

A device that converts thermal energy into mechanical work.

Energy Efficiency Ratio (EEF)

A measure where a higher ratio indicates lower operational costs for energy-efficient appliances.