IGCSE Physics: Electricity & Magnetism
Series ciruit
A circuit in which all parts are connected end to end to provide a single path of current.
Parallel circuit
A closed electrical circuit in which the current is divided into two or more paths and then returns via a common path to complete the circuit.
Switch
A device for making, breaking, or changing the connections in an electrical circuit.
Ammeter
A device used to measure current.
Voltmeter
A device used to measure voltage, or electrical potential energy difference.
LDR
A device whose resistance depends on the amount of light. An increase in light causes a decrease in resistance.
Negative
A material has this charge when it gains electrons.
Positive
A material has this charge when it loses electrons.
Thermistor
A resistor that changes its resistance with a change of temperature.
Variable resistor
A resistor whose value can be varied between its minimum and maximum values.
Direct current
Causes electricity to flow in one direction only.
Alternating current
Causes the current to change continuously, with electricity flowing in one direction then the other.
Free electrons
Electrons that are not bound to any particular atom in the structure of the metal, they are free to move at random throughout the metal.
By coilling the iron with wire
How does electromagnetism generated?
When more current flowing through the conductor, the electromagnetism will be stronger
How does the amount of current affect electromagnetism?
When more number of coils are wound around the conductor, the electromagnetism will be stronger
How does the number of coils affect electromagnetism?
When a soft iron core is used by coilling with wire, the electromagnetism will be stronger
How does the type of core affect electromagnetism?
They point to the direction of the magnetic field around the wire.
In the right hand grip rule, what does the fingers indicate?
It points along the direction of the current
In the right hand grip rule, what does the thumb indicate?
Atom
Made up of neutrons and protons which make the nucleus, which is surrounded by fast moving electrons.
Conductors
Materials that conduct electricity well. They are usually metallic.
Insulators
Materials that do not conduct electricity at all. They are usually non-metallic; rubber, glass and many types of plastic.
Electric charge
Measured in coulombs.
Electrons
Negatively charged particles which surround the nucleus of an atom.
Neutron
Neutral particles in the nucleus of an atom.
Proton
Positively charged particles in the nucleus of an atom.
Fixed resistor
Resistors that have a value that cannot be changed.
Voltage
The amount of energy is transferred per coulomb of charge that is passed through the battery. Measured in volts.
Resistance
The opposition posed by a material or a device to the flow of current. Measured in ohms.
Power
The rate at which electrical energy is converted in an appliance. Measured in watts.
Current
The rate of flow of electric charge through a conductor. Measured in amps.
The stronger the magnetic field in electromagnetism
The thicker the wire used in coiling the iron bar?
North and south poles
What are the names of the two magnetic poles of a magnet?
Cobalt, iron, nickel and steel
What are the names the four magnetic materials? In alphabetical order.....
The direction of the magnetic current around a wire can be predicted
What does the right hand grip rule tells you?
They are more and closer together
What happened to the magnetic field lines near the pole areas?
An object which attracts magnetic materials
What is a magnet?
It is just a temporary magnet induced by electricity
What is electromagnet ?
The use of electricity to induce a magnetic effect on a conductor
What is electromagnetism?
The region around the magnet where the magnetic forces act
What is magnetic field?
When like poles are near each other
When do the field lines always repel?
When unlike poles are near each other
When do the the field lines always attract?
From the north pole to the south pole
Where do the magnetic field lines start in a magnet?
