Household Electricity

Definition
-Electric Power : is the rate at which energy is converted into other forms of energy.
-Power : the energy cnverted per second.
-Voltage : is the measure of how much energy the electrons recieve.
-Potential Difference : The difference in e.m.f ( electromotive force ) between two points in an electrical circiut.
-Electric Current : is a flow of electrical charges.
-Resistance : A measure of how much an electrical component opposes the flow of the current.
: It is the ratio of voltage across the component to the current fowing through it.
(R= V/I)

SI Units
-Voltage (Volt/V)
-Current (Ampere/A)
-Resistance (Ohm)
-Power (watt/W)
-Energy (Joules/J)
-Commercial unit for energy :
-kiloWattshour (kWh)

Formulas
V=IR,
where
V = Voltage (Volt),
I = Current (Ampere) ,
R = Resistance ( Ohm )



P = IV,
where
P = Power (W)
V= Voltage (V)
I = Current (A)

Units of Energy
Energy consumed ( in kWh) = Power ( in kW) x Time ( in hours)

Calculating the Cost of Electrical Energy
Cost of Electrical Energy = Units of Electrical Energy Used (kWh) x Cost Per Unit

* Notes
-Ammeter is connected in series.
-Voltmeter is connected in parallel.
-Resistors are used to :
1) Control the amount ofcurrent
2)Direct Current
3) Increases voltages
4)Converts electrical energy to other forms.
- Resistors ( Variable & Fixed )
- Current produces effects such as :
-Heating,
-Magnetic ,
-Chemical

thats all for now !! xD
Good luck for your coming exams .......
Jiayousss too , ok ?? =D
Will give more detailed information nxt time.... xD