Physics: Speed, Velocity, Acceleration, Forces, and Energy

Comprehensive vocabulary flashcards covering basic physics concepts including motion, forces, work, energy, and thermal transfer methods based on lecture notes.

Speed

The distance covered by an object in per unit time, measured in $m/s$. It is a scalar quantity as it has only magnitude.

Velocity

The displacement of an object in per unit time, measured in $m/s$. It is a vector quantity as it has both magnitude and direction.

Acceleration

The increase of velocity of an object in per unit time, calculated as $a = \frac{v - v_1}{t}$ and measured in $m/s^2$.

Retardation / Deceleration

The decrease of velocity in per unit time, measured in $m/s^2$.

Force

A push or pull acting on an object, measured in $N$ (Newton). Examples include weight, friction, and air resistance.

Weight (W)

The product of mass ($m$) and gravitational acceleration ($g$), calculated as $W = m \times g$. On Earth, $g$ is approximately $10\,N/kg$.

Friction

A resistive force that tries to stop materials sliding past each other.

Terminal Velocity

The steady speed reached by a falling object (like a skydiver) when the gravitational force (weight) and air resistance become balanced.

Newton's First Law of Motion

States that if an object has no force on it, a still object will remain still and a moving object will move at a steady speed in a straight line.

Resultant Force

The combined effect of two or more forces acting on an object.

Work

The product of the force applied to an object and the displacement of the object in the direction of the force, calculated as $W = F \times d$ and measured in Joules ($J$).

Joule (J)

The unit of work and energy, where $1\,J = 1\,Nm$.

Energy

The capability of doing work, measured in Joules ($J$).

Law of Conservation of Energy

States that energy cannot be created or destroyed, only changed from one type to another.

Gravitational Potential Energy (GPE)

Energy stored in an object at a height, calculated as $E_p = m \times g \times h$.

Kinetic Energy (KE)

The energy of a moving object, calculated as $E_k = \frac{1}{2} \times m \times v^2$.

Thermal Conduction

The transfer of heat through solid materials from one particle or atom to another via vibrations or direct contact.

Convection

The heat transfer process in liquids and gases where particles circulate from hot areas to cool areas carrying heat with them.

Convection Current

The circulation of liquid or gas particles caused by the rising of warm, less dense material and the sinking of cooler, denser material.

Thermal Radiation

Heat transferred through empty space as electromagnetic waves, such as sun rays.

Conductor

Materials that transfer heat easily, such as metals like copper, aluminium, and iron.

Insulator

Materials that do not transfer heat easily, such as wood, plastic, rubber, glass, and air.

Vacuum Flask Stopper

A component designed to reduce heat loss by preventing air from rising, thereby minimizing convection.