4) Electricity and Magnetism Flashcards
Define Magnetic poles
Magnetic poles are the regions on the ends of a magnet , where there are the magnetic field lines that either emerge from it, or are directed towards it.
Define Magnets
Magnets are materials that can produce their own magnetic fields and hence are able to attract magnetic substances towards them.
Define Magnetic materials:
Magnetic materials are substances that get attracted towards a magnet
Define Domains:
Magnetic domains are regions within a magnetic material in which the magnetisation is present in a uniform direction
Domain:
A domain is a region inside of a material where groups of magnetic moments naturally align in the same direction.
Define induced magnetism:
When a magnetic substance is brought close to a magnet, it stays attracted to the magnet as long as it is not pulled away from the magnet’s magnetic field. So, we say that the magnetism is induced in the magnetic material as long as it is in the magnets magnetic field.
Define Temporary magnets:
Temporary magnets are made up of soft ion and stay magnetised for some time.
Define Permanent magnets:
Permanent magnets retain their magnetic properties even in the absence of an inducing field or current
Define Electromagnets:
Electromagnets are magnets in which their magnetic field is produced due to an electric current. They usually have iron cores and lose their magnetism when the electric current through them is stopped.
Define Magnetic field:
:It is the region around a magnetic material within which the force of magnetism acts on magnetic materials.
Define Bar magnets:
Bar magnets that are rectangular in shape and have permanent magnetic properties and are made from the ferromagnetic substances
Define Magnetic field lines:
magnetic field lines are imaginary lines around the magnet and their direction is always from the North to South pole of the magnet These are more concentrated towards the poles and never overlap each other
Define Compass:
A compass has a magnetic needle that always points in the North-South direction. The red painted part of it indicates North. Hence is used to find direction while navigating or even to find the direction of magnetic field lines , if placed near a permanent magnet.
Define Iron filings:
These are small shavings of a ferromagnetic material
Define Electric charge:
An electric charge is a basic physical property that causes objects to feel attracted or repelled towards each other
Define Positive charge:
A positive charge exists when the number of protons exceeds the number of electrons .
Electric Field:
An electric field as a region in which an electric charge experiences a force
Define Negative charge:
A negative charge exists when the number of protons is less than the number of electrons .
Define Electrostatic charge:
Electrostatic charge is a charge that is developed on ungrounded or insulating surfaces, as a result of either a deficiency or an excess of electrons .
Define A point charge:
A point charge is a hypothetical charge located at a single point in space .It only exists in theory and cannot be measured.
Define A conducting sphere:
A conducting sphere is a sphere that has the charge present only on its surface
Define Electrical conductors:
Electrical conductors are substances or material that allow electricity to flow through them .
Define Electrical insulators:
Electrical insulators are substances or material that do not allow electricity to flow through them .
Define Electric current:
An Electrical current is defined as the rate at which the charge flows.
Define Conventional current:
Conventional current assumes that current flows out of the positive terminal, through the circuit and into the negative terminal of the source.
Define Ammeter:
:It is an instrument to measure the electric current
Define Alternating current:
An alternating current is an electric current that periodically reverses it’s direction and changes it’s magnitude continuously with time
Define Direct current:
Direct current is the one-directional flow of electric charge
Define Electromotive force:
It is the electrical work done by a source in moving a unit charge around a complete circuit
Define Potential difference:
It is the work done by a unit charge passing through a component
Define Electrical power:
It is the rate at which electrical energy is transferred by an electric circuit.
Define Kilowatt-hour (kWh):
It is a unit of energy and this term tells us that one kilowatt (1 kW) of power is spent in one hour (1 h) of time
