Foundations of electricity Flashcards
what are the two types of electricity and explain them.
Electricity is a type of energy.
There are two types
static - this type of electricity is when the energy builds up somewhere
current - this type of electricity flows from one place to another. That flows from negative to positive charge.
Explain how atoms become charged and their attractions.
Atoms consist of protons electrons and neutrons and often have the same number of protons and nuetrons
if they lose an electron they become net positively charged
if they gain an electron they become net negatively charged
Like charges repel e.g.
+ve <- -> +ve
Oppositve charges attract e.g.
+ve -> <- -ve
why is it important to understand about static electricity when it comes to components
Our hands always carry some form of charge and so does every surface.
It is important to keep components that we work with on solid surfaces otherwise they could be damaged.
What is voltage and what are the units that it is measured in
it is the force that makes electrons move from one point to another in a wire. and is the electric potential between two points.
it is measured in volts using a volt metre.
what is current and what is it measured in.
Flows in opposite direction to electrons.
Current is just the rate of flow of electric charge
measured in ampoules.
What is the difference between the current in DC and ac current
dc current is direct current and maintains at a level while the alternating current switches the voltage doesnt stay steady with time.
We deal with DC current.
what is resistance and what is it measured in
measure of difficulty of passing electric current through the system
measured in ohms.
what is Ohms law
Voltage = Resitance * Current
How to read the bands on a resistor
in a 4 band
1st band = 1st digit
2nd band = 2nd digit
3rd band = multiplier
4th band = tolerance
in a 5 band
1st band = 1st digit
2nd band = 2nd digit
3rd band = 3rd digit
4th band = multiplier
5th band = tolerance
