Practical Electricity Flashcards
What are the uses of electricity?
Heating effect ( iron, kettle, toaster) Magnetic effect ( fan, washing machine, bell)
Equation for electrical power? unit?
Electrical power = current X voltage
unit: W (watts)
Formula for energy
Energy = voltage X current X time
What is kilowatt - hour (Kwhr)
It is the unit of energy consumed at home
Formula for Kwhr?
Energy = power X time
Hazard of damaged insulation
The live wire becomes exposed which is then potential danger for someone getting electrocuted if the wire is accidentally touched or makes contact with the metal casing of the appliance. (Cables with double insulation should be used)
Hazards of overheating cables
The excessive flow of current causes overheating of the cables which may eventually lead to a fire
Hazard of damp conditions
If a person accidentally touches the live wire or if water flows to the live wire the person is at high risk of being electrocuted. In a damp environment water vapour condenses on the electrical appliance around
Use of fuses
A fuse is a safety device that is used to protect electrical appliances from damage due to excess flow of current.
Uses of circuit breakers
Functions just like a fuse but it does not need to be replaced from time to time in case of excessive flow of current
Uses of fuse ratings
Fuses exist in different forms so that they suit best for a specific use
Live wire
Is the only wire which is at a high voltage. It allows alternating current
Earth wire
It carries excess current to the earth when a fault is developed in the circuit. It protects a person from getting an electric shock
Neutral wire
Almost at 0V. The neutral wire completes the circuit for a current to flow through the appliance
How are the electrical appliances in homes arranged?
Parallel circuit