Electricity And Lighting (Chapter 11) Flashcards
Why is electric very important?
It is a very important part of everyday life. It is used in homes and workplaces for many purpose
What are conductors?
Are material containing eclectic charges which can flow freely
Example of conductor
Metal, sliver, copper
What are insulator?
Are material in which eclectic charges can not flow freely
Example of insulator
Wood, plastic, rubber, glass
What are Semi conductors?
Are material that is both good conductors and insulator
Example of Semi conductors
Silicon, germanium
What is one use of a Conductors?
To make electricity wires
What is one use of Insulator?
To cover electrical wires and to ensure certain appliances
What is one use of Semi conductors?
To make Electrionic components
What is a Electric circuits?
Is a complete path or loop through electrons can flow from a source and then return to the source
What are the main importance electrical quantities?
Voltage, Current, Resistance and Power
What is voltage SI unit and symbol?
The SI unit is volt and the symbol is V
What is Current SI unit and symbol?
The SI unit is ampere and the symbol is A
What is Resistance SI unit and symbol?
The SI unit is ohm and the symbol is a horse shoe
What is Power SI unit and symbol?
The SI unit is watt and the symbol is W
How to calculate Voltage?
Voltage=Current(I)×Resistances(R)
How to calculate Power?
Power=Voltage(V) × Current (I)
How to calculate Resistance?
Resistance=Voltage (V) ÷ Current (C)
What colour is used for Earth wires?
Green and yellow
What colour is used for live wires?
Brown
What colour is used for Neutral wires?
Blue
What happens when a circuit is overload?
There will be overheating, destroying of insulation and even causing fires
What is a fuse?
Is a short wire that melts and breaks a circuit when the current exceeds a certain value
How does a fuse protect an appliances such as a hairdryer?
