A-level Physics/Glossary of Terms
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Definitions of keywords and terms that you will need to know.
Zero on the thermodynamic temperature scale, or 0 K (kelvin), where a substance has minimum internal energy, and is the coldest possible temperature. It is equal to -273.15 degrees Celsius.
The (instantaneous) rate of change of velocity in respects to time.
Two equal, opposite and parallel forces which create rotational force.
A vector quantity, the distance something is from its initial position, in a given direction
Density is the mass of a body per unit volume
The stored ability to do work
The change in length of an object when a force is applied to it
A force causes a mass to change motion
Gravitational Potential Energy
the energy an object has due to its relative position above the ground. Found by mass x gravity (or gravitational field strength) x height
is a form of energy transfer, also known as ‘Thermal Energy’.
an approximation that states that the extension of a spring is in direct proportion with the load added to it as long as this load does not exceed the elastic limit.
The SI unit of work done, or energy. One joule is the work done when a force of one newton moves an object one metre.
The energy an object possesses due to its motion, given by KE = 0.5 x mass x velocity²
Unit in which force is measured. Symbol “N”. One Newton is the force required to give a mass of 1kg an acceleration of 1ms^-2
The time taken for one complete oscillation. Denoted by ‘T’. T=1/f
The rate at which work is done.
The load applied to an object per unit surface area.
The work done in moving a unit positive charge from one point to the other. The unit is volt.
A quantity with magnitude but no direction.
A scalar quantity, speed = distance / time
NB s can also mean displacement.
Stopping distance = Thinking distance + Braking distance
thinking distance (distance traveled while reacting) = time taken to react X velocity
braking distance (distance traveled while braking)
maximum velocity a body can travel. When resistive forces = driving force, acceleration = 0, so it cannot travel any faster.
Torque / moment
Moment = force x perpendicular distance from the pivot to the line of action of the force
Torque = one of the forces x the distance between them
A progressive wave that trasfers energy as a result of oscillations/vibrations.
A force experienced due to the pressure difference of the fluid at the top and bottom of the immersed portion of the body.
A quantity with magnitude and direction.
The (instantaneous) rate of change of displacement with respect to time. Velocity is a vector.
The energy transferred when an object is moved through a distance by a force. Can be calculated by multiplying the force involved by the distance moved in the direction of the force.
Alternatively, [work done = transfer of energy]. i.e, work is done when energy is transferred from one form to another.
Stress per unit Strain, units: Pascals or N/m2