Ch 13 - Electrical System Flashcards
The parts of an electrical system are called ____.
electrical components!
The main components of an electrical system:
- cell (battery)
- wires
- electrical device (eg bulb)
Closed circuit provides …
…a continuous path for electric current to flow.
Open circuit occurs when…
…there is a gap in the circuit and electricity cannot flow from one end of the cell to the other.
Electrical appliances can work in a ____ circuit.
CLOSED
Electrical appliances cannot work in an ____ circuit.
OPEN
How many paths in a series circuit?
There is only ONE path through which electricity can flow through.
How many paths in a parallel circuit?
There are SEVERAL paths through which electricity can flow through.
Define electric current.
a measure of the rate of flow of electric charge through a conductor.
SI unit of Electric Current?
ampere (A)
Conventional Current
vs.
Electron Flow
positive to negative
&
negative to positive
How to measure electric current?
Ammeter
How to connect an ammeter?
In series arrangement!
Define potential difference.
the amount of energy needed to move one unit of electric charge from one point to another
Potential difference is also v____.
voltage!!!
SI unit of potential difference/voltage?
volt (V)
How to measure potential difference?
voltmeter
How to connect voltmeter?
In parallel arrangement :)
Define resistance.
A measure of the degree to which an electrical component opposes the flow of electric current.
SI unit of resistance.
ohm (Ω)
How to find resistance (using voltage and current)?
R = V/I
Types of resistors.
- fixed resistors
- variable resistors (rheostats)
Uses/examples of rheostats.
- light dimmer
- volume control on music player
- speed control of a model train
Formula of resistance in a series circuit. (use R)
RT = R1+R2
In series circuit, the effective resistance is always _____ than the largest of the individual resistances.
GREATERRR 👀
Formula of resistance in a parallel circuit. (use R)
1/RT = 1/R1 + 1/R2
In parallel circuit, the effective resistance is always _____ than the smallest of the individual resistances.
SMALLER 🤏
The 3 effects of an electric current??
- chemical effect 🧪
- magnetic effect 🧲
- heating effect 🔥
Use of chemical effect of electric current?
electrolysis and electroplating
What is electrolysis?
When electricity is used to break down compounds into its elements.
Examples of electrolysis.
aluminium from bauxite
What is electroplating?
coating objects in metal 😂
Metals that are used for electroplating?
copper, chromium, silver, gold, nickel
To increase the strength of magnetic effect:
- Increase the number of turns of the wire (solenoids)
- Increasing the current
Examples of magnetic effect used in real life.
- magnetic cranes
- electric bells
- electric motors (vacuum cleaners and fans)
In heating appliances, the heating element is made of materials with _____ resistance.
HIGHHH HEE HEE
Examples of materials with high resistance.
nichrome (alloy of nickel), iron, chromium
1 kW = ______ W ?
1 kW = 1,000 W
Define power.
The amount of electrical energy converted to other forms of energy per second by the component.
SI unit of power?
watt (W)
Unit used to measure amount of electricity used in homes.
kilowatt-hour (kWh)
Formula for energyy
energy = power x time
Formula for power
power = energy / time
2 electric hazards
electrical fire & electric shock
What can cause electrical fire?
- short circuit
- overloading
What can cause electric shock?
- damaged insulation
- wet conditions
2 safety feature found in household electric circuits
fuse & circuit breaker
fuse VS. circuit breaker
must be replaced after used
VS.
needs to be reset after use
