Year 7 Physics Revision - Key Vocabulary

Vocabulary flashcards covering key definitions and concepts from the Year 7 Physics Revision Sheet.

Physics

The branch of science that studies matter, energy, motion, and the forces that act between them.

Force

A push or a pull that can change the shape, speed, or direction of an object, measured in newtons ($\text{N}$).

Contact Forces

Forces that act only when two objects are physically touching each other.

Non-contact Forces

Forces that act even when objects are not touching each other ("at a distance").

Applied Force

A push or pull applied directly to an object, such as pushing a box.

Frictional Force

A force that opposes the motion between two touching surfaces, such as brakes slowing a bicycle.

Normal Force

A surface pushing back on an object resting on it.

Tension Force

A pulling force carried through a rope or string.

Air Resistance (Drag)

A type of friction between a moving object and the air that always acts opposite to the direction of motion.

Gravitational Force

A force that pulls any two objects with mass towards each other, such as Earth pulling objects down.

Magnetic Force

A non-contact force that attracts or repels magnetic materials.

Electrostatic Force

A non-contact attraction or repulsion between electric charges.

Balanced Forces

Forces acting on an object that are equal in size and opposite in direction, resulting in a net force of $0\,\text{N}$ and no change in motion.

Unbalanced Forces

Forces acting on an object that are not equal, producing a net force that causes a change in motion (start, stop, speed up, slow down, or change direction).

Net Force

The overall combined force acting on an object, found by adding forces in the same direction or subtracting forces in opposite directions.

Mass

The amount of matter in an object, measured in kilograms ($\text{kg}$) with a balance, which stays the same everywhere in the universe.

Weight

The force of gravity acting on an object's mass, measured in newtons ($\text{N}$) with a spring balance or newton meter, which changes depending on local gravitational field strength.

Weight Formula

The formula $W = m \times g$, where $W$ is weight in newtons ($\text{N}$), $m$ is mass in kilograms ($\text{kg}$), and $g$ is gravitational field strength in $\text{N/kg}$.

Gravitational Field Strength ($g$)

The gravitational force per unit mass at a location, equal to approximately $9.8\text{--}10\,\text{N/kg}$ on Earth, $1.6\,\text{N/kg}$ on the Moon, and $0\,\text{N/kg}$ in space.

Streamlining

Giving an object a smooth, pointed shape to reduce air resistance as it moves through the air.