Topic 2 - Electricity Flashcards
What is the unit for resistance?
Ohms (Ω)
What is The National Grid?
A system of cables and transformers linking power stations to consumers.
What is potential difference?
Potential difference is a measure of how much energy is transferred between two points in a circuit.
What are step-up transformers used for?
To increase the voltage from the power station to the transmission cables.
What are step-down transformers used for?
To decrease the voltage to a much lower value for domestic use
What is the rule regarding energy in electrical appliances?
The amount of energy an appliance transfers depends on how long the appliance is switched on for and the power of the appliance.
How can objects become electrically charged?
When certain insulating materials are rubbed against each other they become electrically charged (gain / loss of electrons)
What are electric fields?
A region surrounding a charged object which causes a force to be exerted on any charged object placed within the field.
How does force exerted by electric fields change with distance?
- The electric field is strongest close to the charged object.
- The further away from the charged object, the weaker the field.
- Therefore, the force gets stronger as the distance between the objects decreases.
What is the unit for charge flow?
Coulombs, C
