Definition of physical quantities

Friction

A force opposing motion, it arises due to interactions between two surfaces (when you’re trying to move an object for ex)

Weight

The gravitational force exerted by the system

Mass

The quantity of matter within an object

Archimedes’ Principle

When a body is completely or partially immersed in a fluid, the fluid exerts an upwards force on the body equal to the weight of the fluid displaced by the body

Frequency

Number of peaks or troughs that pass by a fixed point in one second

Wavelength

Distance between adjacent peaks or troughs

Electric current

How many charges are flowing between two points in a time t

Resistance

The measure of the opposition to the flow of current in a circuit or a material

Power

Rate at which energy is consumed

Electric flux

The total amount of electric field which is “flowing” through a given area

Magnetic flux

The number of magnetic field lines which are passing through a given area

Focal length

Distance between the center of the lens and the focal point

Refractive index

Index that characterises the speed of light in the medium of propagation

Specific heat capacity

The heat (energy) required to change the temperature of 1 kilogram of a material by 1 degree Kelvin

Average speed

The total distance over the total time

Average velocity

The total displacement over the total time

Electric field

A region around a charged particle or object within which an attractive or repulsive force would be exerted on another charged particle or object

Electric potential

The amount of work/energy needed per unit of electric charge to move the charge to a different point in the field

Pascal’s principle

The pressure change applied at one point in an enclosed incompressible fluid is transmitted undiminished to every part of the fluid and to the walls of the container

Temperature

measure of the total energy of motion of the particles that constitute it

Heat conduction

Transfer of kinetic energy between atoms or molecules of a solid

Heat convection

At the boundary where a fluid is in contact with a material, heat is exchanged between the surface and the boundary layer through the transfer of kinetic energy

Gauss’ Law

The electric flux through any closed surface is equal to the charge enclosed by the permittivity.

Wave

A disturbance that transfers energy from one place to another without any net motion of the medium through which it passes

Transverse wave

The displacement of particles is at right angles to the direction of the propagation

Longitudinal waves

The displacement of the particles is parallel to the direction of the propagation of the wave

Period of a wave

Measure of how long it would take for a single cycle of the wave to pass by a fixed point

Harmonic wave

Wave with a constant frequency and where the particles are displaced up and down by the same amount

Fermat’s principle

The path between 2 points taken by a beam of light is the one which is traversed in the least time, not the least distance