Electricity

Electricity

7.1

Electricity

ENERGY

Energy means the ability to do work
The S.I.unit for energy is joule (J)

Forms of energy

Sound energy
Kinetic energy
Electrical energy
Gravitational potential energy
Elastic potential energy
Light energy
Nuclear energy
Heat energy
Chemical energy

Sources of energy

The Sun
Geothermal
Water
Biomass
Fossil fuel
Radioactive substances
Wave
Wind

Electrostatic Charges

Electric charges consist of positive charges and negative charges
The repulsion among these charges are called electrostatic forces
Electroscope is used to detect the existence of electric charges on an object

Electric current

\(\downarrow\)

Electric current can be defined as the rate of flow of electric charges through a conductor

Current, Voltage and Resistance

S.I unit for electric current is ampere(A) - measured by ammeter
The voltage is the potential difference between two points, volt(V) - measured by voltmeter
The unit for measuring resistance is ohm (Ω)
The relationship between current, voltage and resistance is Ohm's Law

\(V=IR\)