Electrical Systems Flashcards
(15 cards)
What is electricity
Form of energy caused by flow of electrical charges
In metals, free moving electrons flow to conduct electricity
What is electrical circuit
Path where electrical charges flow
What is a short circuit
When a current flows through a path of negligible resistance. No current flows through the light bulb
Why is a short circuit dangerous
A short circuit can result in a very large current, which can generate enough heat to start a fire.
What is an electrical current
Rate at which electrical charges flow
SI Unit for electrical current
Ampere
Written as A
What is a conventional current
In closed circuit, current flows from positive to negative terminal
What is electron flow
Electricity is a result of electrons flowing from negative to positive terminal
How to measure current
Ammeter.
It is connected in series to circuit.
Negligible resistance
How to read ammeter
Nearest half of smallest division
Define potential difference
The potential difference between 2 points in an electrical circuit is the amount of energy needed to move a unit charge from one point to another
SI unit for potential difference
Volt
Written as V
Instrument to measure potential difference
Voltmeter
It is connected in parallel to (across) the component. Voltmeter has a very large resistance and does not allow any current to flow through
How to read voltmeter
Nearest half of smallest division
