Semester 2 Flashcards
The assumptions of the kinetic particle model
- all matter is made up of many very small particles (atoms or molecules)
- the particles are in constant motion.
- no kinetic energy is lost or gained overall during collisions between particles.
- there are forces of attraction and repulsion between the particles in the model.
- the distance between particles in a gas is much larger compared to a solid.
Kinetic particle model
Model that describes or explains the workings of a motion of particles inside a substance.
What is the coldest possible temperature?
Absolute zero. (-273.15°C)
Solids
- fixed shape
- exert repulsive and attractive forces on each other with the attractive forces being more stronger.
liquid
- balance of attractive and repulsive forces
- Particles can move more freely
- fixed volume with no fixed shape
- particles collide
- in general, volume increases with temperature (water is the exception)
Gas
- constant random motion
- more rapidly
- colliding with each other and container
- no fixed volume
- repulsive forces are stronger than attractive forces
zeroth Law of Thermodynamics
states that if two bodies are each in thermal equilibrium with some third body, then they are also in equilibrium with each other.
What happens to the energy when the phase of the matter changes?
The energy absorbed or released depends on the specific phase change.
Ammeter
a device used for measuring the rate of flow of charge (current) in a circuit.
Charge
one of the basic properties of the elementary particles (electrons and protons) which can be negative or positive, and is in discrete units (whole number).
Conventional current
the motion of charge in the same direction as the positive charge flow; opposite to electron flow.
Coulomb
a measure of electric charge.
1 Coulomb = 6.25 x 10^18 elementary charges
Electrical current
a rate of motion of electrical charge carriers from one part of a conductor to another (Symbol: I; SI unit: ampere (A)
Conventional current
the motion of charge in the same direction as the positive charge flow; opposite to the electron flow.
Ammeter
a device measuring the rate of flow of charge (current) in a circuit.
Electrical potential
the amount of work needed to move a unit (1 C) of charge from one point to another, or the electrical potential energy per unit of charge (symbol: V; SI unit: volts (V).
Electrical potential energy
amount of energy stored in a charge; or the capacity of the charge carriers to do work due to their position in an electrical circuit (Symbol: U; units: Joules (J)
Law of Conservation of charge
The net amount of charge produced in any transfer is zero, and charge cannot be created nor destroyed.
Ohm’s law
law stating that electric current is proportional to voltage and inversely proportional to resistance.
First law of thermodynamics
during an interaction between a system and its surroundings, the amount of energy gained by the system must be exactly equal to the amount of energy lost by the surroundings
Transmutation
conversion of one chemical element into another
metastable
condition where a system can persist for a long time, but it is not in the most stable configuration possible.
Electrical resistance
opposition to the flow of current in a circuit measured as a ratio of the voltage applied to the electric current that flows through it.
Electromotive force
a difference in electrical potential that produces an electrical current (Symbol: EMF, SI units: Volts (V)
electrostatic repulsion
the phenomena that two like charged particles repel.
Ohmic devices
devices that follow Ohm’s law
Elementary charge
the magnitude of the electric charge carried by a single proton or electron.
Parallel connection
connection in which all the positive terminals of the cells are connected together, and all the negative terminals are connected as well.
Potential difference
the difference in electrical potentials between 2 points in an electric field.
Power
the rate at which work is done
Resistivity
a fundamental property of matter that quantifies how strongly a given material opposes the flow of electric current.
Resistor
a device that reduces the flow of charge (current) in a circuit
Series
scribes an electrical circuit where components are connected along a single path.
Voltage
a measure of electrical potential energy per unit charge, measured in joules per coulomb; often referred to as electric potential difference
Voltmeter
an instrument used for measuring electric potential difference between two points in an electric circuit.
Volts
a unit of electric potential or voltage, equivalent to 1 joule per coulomb of charge.
Absolute zero
the lowest theoretically possible temperature, at which the motion of particles constituting heat would be minimal. It is zero on the Kelvin scale.
Calorimetry
the science of measuring the amount of heat transferred between objects or in a chemical reaction.
Conduction
a process in which heat is directly transferred or transmitted through a substance due to a temperature difference between neighboring regions, without movement of any matter.
Convection
a transfer of heat caused by the movement within a fluid of the hotter and less dense material rising, and colder, denser material, which sinks, under the influence of gravity.
Heat
the internal energy transferred throughout the heating process.
radiation
the transfer of energy in the form of electromagnetic waves or moving subatomic particles.
specific heat capacity
the thermal energy required to raise the temperature of 1kg of a substance by 1 degree.
temperature
a measurement of the warmth or coldness of an object or substance with reference to some standard value (e.g. celsius temperature).
thermal energy
the internal energy present in a system due to its temperature. It doesn’t include nuclear energy (Symbol: U; unite: Joule (J).
Thermal equilibrium
the situation when there is no net exchange of thermal energy between any components of a system, i.e. the components have the same temperature and the average kinetic energy of the particles is equal.
Zeroth law of thermal equilibrium
if two bodies are in thermal equilibrium with a third body, they are in thermal equilibrium.
Alpha decay
the emission of a 4He2 nucleus (2 protons, 2 neutrons) from the parent nucleus
Alpha radiation
stream of particles each consisting of two protons and two neutrons tightly bounded together, emitted from the nucleus of some radionuclides.
Beta negative decay
emission of beta negative particles (electrons) from the parent nucleus.
beta positive decay
emission of beta positive particles (positrons) from the parent nucleus
gamma decay
a form of radioactivity in which an unstable atomic nucleus loses energy by emitting gamma radiation
half-life
the time taken for half the radioactive atoms in a sample to decay.
ionising radiation
radiation that can remove an electron from an atom and create a heavy positive ion and free electron
Nuclear fission
a nuclear reaction in which a large unstable nucleus splits, forming two (or more) smaller, more stable nuclei and releasing neutrons and energy.
Nuclear fusion
a nuclear reaction in which two or more light atomic nuclei react (fuse) to form one or more different, heavier atomic nuclei and subatomic particles
nuclear stability
a measure of the stability of an isotope determined from the neutron/proton ratio and the total number of nucleons in the nucleus.
radioactive
describes substances which have nuclei with an excess of energy and spontaneously emit radiation to reduce to excess energy.
stable
characteristic of nuclides that are not radioactive and so (unlike radionuclides) do not spontaneously undergo radioactive decay.
strong nuclear force
force that acts over very small distances in the nucleus to hold the nucleons together against the repulsive electrostatic forces between the positively charged protons. It is one of the four fundamental forces.
Nuclide
distinct kind of atom or nucleus characterized by a specific number of protons and neutrons.
How to calculate all the factors in Ohm’s law in a series circuit
- Total resistance = Sum of resistance in components
- Total voltage = Sum of voltage in components
- Total current = same current of any individual component
How to calculate all the factors in Ohm’s law in a parallel circuit
- 1/Total resistance = inverse sum of resistance (1/R)
- Total Voltage =same voltage of any individual component
- Total current = sum of current
