Definitions Flashcards
Kinetic energy
The energy associated with motion of an object
Gravitational Potential Energy
The energy an object has due to its position in a gravitational field
Work done
The amount of energy converted from one form to another
Heat
The amount of energy transferred from one place to another due to a temperature difference
Efficiency
The useful work done divided by total energy put in
Power
The amount of work done per unit time
Velocity
The distance an object travels in a certain direction in 1 second
Acceleration
The change in velocity in 1 second
Terminal Speed
The constant speed of an object when the driving force is balanced by friction
Amplitude
The maximum distance of the oscillation, from the rest point
Period
The time for one complete oscillation
Wavelength
The distance for one complete oscillation
Frequency
The number of complete oscillations per second
Longitudinal wave
A wave where the direction of oscillation is parallel to the direction of energy transferred
Transverse wave
A wave where the direction of oscillation is perpendicular to the direction of energy transferred
Isotope
An atom with the same number of protons but different number of neutrons
Density
The amount of mass per unit volume
Pressure
The force per unit area
Conduction
The transfer of KE when atoms or molecules collide
Convection
The movement of a fluid as a result of density differences
Radiation
The transfer of energy using electromagnetic waves
Brownian Motion
The random motion of atoms and molecules in a fluid
Fluid
A gas or a liquid
Gamma waves
An electromagnetic wave with the highest frequency
Ultrasound
Sound waves with a frequency above 20000Hz
Weight
The force on an object due to gravity
Refraction
The change of direction of a wave when it moves from one material into another due to the change of speed
Why does change of speed occur in refraction?
Due to the change of density in the materials
Critical angle
The angle of incidence which produces an angle of refraction of 90 deg
Total internal reflection
The reflection of a wave when it meets a boundary at an angle greater than the critical angle
Current
Rate of flow of (positive) charge
Voltage
The electrical potential energy difference for 1 Coulomb of charge
Resistance
The voltage per unit current
Thermal energy
All potential energy + KE particles inside an object
Half life
The time for half of the nuclei to decay
Ohmic Behaviour
The resistance does NOT change as the current changes / The current-voltage graph is a straight line
Orbital Period
The time taken for a planet to orbit the Sun once
