Physical Quantities, Measurement Techniques, and Motion

Vocabulary flashcards covering physical quantities, vectors, scalars, and motion based on the Cambridge IGCSE Physics syllabus.

Scalar Quantity

A quantity that has magnitude (size) only.

Vector Quantity

A quantity that has magnitude and direction.

Scalar Quantities (Syllabus List)

Distance, speed, time, mass, energy, and temperature.

Vector Quantities (Syllabus List)

Force, weight, velocity, acceleration, momentum, electric field strength, and gravitational field strength.

Speed

Distance travelled per unit time, given by the equation $v = \frac{S}{t}$.

Velocity

Speed in a given direction.

Average Speed

Calculated using the equation $\text{average speed} = \frac{\text{total distance travelled}}{\text{total time taken}}$.

Acceleration

Change in velocity per unit time, given by the equation $a = \frac{\Delta v}{\Delta t}$.

Gradient of a Distance-Time Graph

Calculates the speed of an object along a straight-line section of the graph.

Area Under a Speed-Time Graph

Determines the distance travelled for motion with constant speed or constant acceleration.

Gradient of a Speed-Time Graph

Calculates the acceleration of an object.

Acceleration of Free Fall ($g$)

The acceleration for an object near the surface of the Earth, which is approximately constant and approximately $9.8\,\text{m/s}^2$.

Deceleration

A negative acceleration.