Electricity And Energy Flashcards
Give 4 examples of electric fields in use
Laser printing
Paint spraying
Cling film
Dust removal
Define electric current
Charge passing per unit time
When dc charge moves around a circuit what direction does it move in only one direction?
Yes
How does dc charge show on an oscilloscope?
Horizontal flat line
Where does dc come from?
Batteries
How do ac Charges move
Back and forth
is an ac charge alternating?
Yes moves from negative to positive them back
What shape does an ac current give on an oscilloscope?
A wave
Where does ac come from?
Mains supply (50hz)
What effect do resistors have on both current types? (Ac and dc)
None
What do capacitors do to dc current?
Bring current to zero
What do capacitors do to ac current?
Make ac current directly proportional to frequency
What effect do lamps have on ac and dc currents?
No effect on either
What will make lamps flash faster?
If ac frequency is increased
What do diodes do to dc current
To pass in only one direction
What do diodes do to ac current
Allow only half to pass
Define work done
The amount of energy transferred by potential difference, voltage,
Define potential difference
The work done per unit of charge
Define resistance
The opposition to electric current
What is an ammeter used to measure
The flow of charge
Where must an ammeter be connected to?
A series circuit to measure current
What is current measured in?
Amperes
What’s a go.gmeter used for?
Measuring potential difference
What is voltage measured in
Volts
How do you measure the resistance of a component ?
With an ohmeter not connected to power