science unit 3 Flashcards
monday revision
In series
If components in a circuit are on the same loop.
Field
The area where other objects feel an electrostatic force.
Current:
Flow of electric charge, in amperes (A).
In parallel
If some components are on separate loops.
Electromagnet
A non-permanent magnet turned on and off by controlling the current
through it
Electrons
Tiny particles which are part of atoms and carry a negative charge.
Charged up
When materials are rubbed together, electrons move from one surface to
the other
Negatively charged
An object that has gained electrons as a result of the charging process.
Electrostatic force
Non-contact force between two charged objects.
Positively charged
An object that has lost electrons as a result of the charging process.
The amount of energy shifted from the battery to the moving charge, or
from the charge to circuit components, in volts (V).
Potential difference
voltage
A property of a component, making it difficult for charge to pass through, in ohms (Ω).
Resistance
A material that allows current to flow through it easily, and has a low
resistance.
Electrical conductor
A material that does not allow current to flow easily, and has a high
resistance.
Electrical insulator
Resistance (Ω) = potential difference (V) ÷ current (A).
Resistance equation
A device for measuring potential difference (Voltage).
Voltmeter
A device for measuring current.
Ammeter
This relates the resistance of a component to its voltage and current.
Ohm’s law
Shows how food chains in an ecosystem are linked.
Food web
Part of a food web, starting with a producer, ending with a top predator.
Food chain
Ecosystem
The living things in a given area and their non-living environment.
Environment:
The surrounding air, water and soil where an organism lives.
Population
Group of the same species living in an area.
Producer
Green plant or algae that makes its own food using sunlight
Consumer
An animal that eats other animals or plants.
Decomposer
An organism that breaks down dead plant and animal material so
nutrients can be recycled back to the soil or water.
Competition
When two or more living things struggle against each other to get the
same resource.
Evolution
Theory that the animal and plant species living today descended from
species that existed in the past.
Biodiversity
The variety of living things. It is measured as the differences between
individuals of the same species, or the number of different species in an
ecosystem.
Natural selection
Process by which species change over time in response to
environmental changes and competition for resources.
When no more individuals of a species remain
Extinct
What all substances are made up of, and which contain only one type of
atom.
Elements
A substance, normally a liquid, that dissolves another substance
Solvent
A substance that can dissolve in a liquid.
Solute
Mixture formed when a solvent dissolves a solute.
Solution
Capable of dissolving in a liquid
Soluble
Maximum mass of solute that dissolves in a certain volume of solvent.
Solubility
Single type of material with nothing mixed in.
Pure substance
Two or more pure substances mixed together, whose properties are
different to the individual substances
Mixture
Separating substances using a filter to produce a filtrate (solution) and
residue.
Filtration
Distillation
Separating substances by boiling and condensing liquids.
Evaporation
A way to separate a solid dissolved in a liquid by the liquid turning into a
gas
Chromatography
Used to separate different coloured substances
Weight
The force of gravity on an object. Measured in Newtons (N).
Non-contact force
One that acts without direct contact.
Mass
The amount of stuff in an object (kg)
Gravitational field strength
The force from gravity on 1 kg (N/kg).
Gravitational Field
The area where other objects feel a gravitational force.
The Universe
The totality of existence, including planets, stars, galaxies, the contents
of intergalactic space, and all matter and energy.
The solar system
Contains the Sun and its planets.
