Electrical Systems Flashcards
What is the symbol for current?
I
What is the SI unit symbol for current?
A
What is an ammeter used for?
To measure the current passing through a component.
How must the ammeter be connected?
In series, positive terminal connected to positive terminal of dry cell.
What is the symbol for volt?
V
What is a voltmeter used for?
To measure potential difference across a component.
How must the voltmeter be connected?
In parallel, positive terminal connected to positive terminal of dry cell.
What is the symbol for resistance?
R
What is the SI unit for resistance?
Ohm.
What is the ohmmeter/multimeter used for?
To measure resistance of a component.
How should the ohmmeter/multimeter be connected?
In parallel to the component.
What are the 3 factors affecting resistance?
- Cross section area
- Length
- Material
What is the formula for potential difference, current and resistance?
Potential difference = current × resistance
What happens to the effective resistance when resistors are connected in series?
It becomes larger than the largest individual resistance.
What happens to the effective resistance when resistors are connected in parallel?
It becomes smaller than the smallest individual resistance.
When the slider of a rheostat is closer to the top terminal, what happens to the resistance?
It is higher.
What are the 4 applications of effects of current?
- Chemical
- Magnetic
- Heating
- Lighting
What is the symbol for power?
P
What is the SI unit of power?
Watt
What is the SI unit symbol for power?
W
What is the symbol, SI unit and SI unit symbol of energy?
E, Kilowatt-hour, kWh
What is the symbol, SI unit and SI unit symbol for power?
P, Kilowatt, kW
What is the symbol, SI unit and SI unit symbol for time?
t, Hour, H
What is the formula for power, volt and current?
Power = VI
What is the formula for energy, power and time?
Energy = power × time
What is the unit for electrical energy used at home?
Kilowatt-hour.
