FA Revision Flashcards
What are the environmental consequences of developing electrical energy production?
There are environmental consequences to develop electrical energy production to meet the needs of an expanding global population.
This addresses the impact of globalisation and sustainability in energy production.
What is a property of electric field lines?
Field lines never intersect each other.
This is a fundamental characteristic of electric fields.
How is the strength of an electric field indicated by field lines?
The field is strong when the lines are close together, and it is weak when the field lines move apart from each other.
The density of field lines correlates directly with field strength.
Where do electric field lines start and end?
The electric field line starts from the positive charge and ends from negative charge.
If the charge is single, they start or end at infinity.
What is the origin of magnetic field lines?
Magnetic field lines appear to emerge or start from the north pole and merge or terminate at the south pole.
Inside the magnet, the direction of the magnetic field lines is from the south pole to the north pole.
What happens to magnetic field lines in a magnet?
Magnetic field lines form a closed-loop.
They never intersect with each other.
How is the strength of a magnetic field indicated?
The magnetic field is stronger at the poles because the field lines are denser near the poles.
This density indicates a stronger magnetic influence.
What experiment demonstrated the origin of the magnetic field from electric current?
Oersted Experiment.
This experiment showed the relationship between electricity and magnetism.
What is a solenoid?
Circular coil of wires.
Solenoids are used to create magnetic fields when electric current flows through them.
What is the formula for the force on a current carrying conductor in a magnetic field?
F = ILB.
Where F is the force, I is the current through the conductor, L is the length of the conductor, and B is the external magnetic field.
What does a DC motor convert?
Converts electrical energy to mechanical energy.
This is essential in various applications of electromagnetism.
What phenomenon causes electric current to be generated from a magnetic field?
Electromagnetic induction.
This occurs when magnetic field lines move through a wire in a solenoid.
What is an application of electromagnetic induction?
AC Generator.
It generates alternating current by converting mechanical energy to electrical energy.
What is the relationship between current, voltage, and power?
Power (P) = Current (I) x Voltage (V).
This relationship helps in understanding electrical systems.
What is resistive heating?
The production of heat due to electric current passing through a conductor.
It results in energy loss in power transmission.
Why is electricity transmitted at high voltage?
To minimize the electric current flowing in the wire for a given power.
This helps reduce resistive heating and economic costs.
What are transformers used for in the power grid?
For stepping up and stepping down the voltage.
This ensures the voltage is at an optimal level for transmission.
