static electricity and electrical currants
TRANSCRIPT
November 5, 2014
1. Define and describe static electricity2. Define and recognize the presence of a
charge3. Distinguish between conductor’s and
insulator’s4. Describe how static electricity is different
than current electricity
Movement of charged particles
Rule 1: Like charges repel one anotherRule 2: Unlike charges attract one
another
Electrons carry negative charges and protons carry positive charges
Electrons can move from atom to atom
An atom that has more electrons is negative
An atom that has less electrons is positive
The imbalance of positive and negative charges
So how do we move electrons from one place to another?
By rubbing them together
The build up of electrons creates a static charge
The jumping of electrons from one object to another creates a static shock
Build up of neg. charges and pos. charges on opposite poles
The positive part of one object will be attracted and move toward the negative charge of the other object
TRIBOELECTRIC SERIES your hand
glassyour hairnylonwoolfursilkpapercottonhard rubberpolyesterpolyvinylchloride plastic
Items near the bottom tend to gain negative charges when rubbed with something near the top
Clouds become negatively charged relative to the ground
Lightning appear as charges are exchanged between the clouds and the ground
Currents made of flowing electrons, in one direction
Ampere (A) – the rate of electrical flow
Coulomb (C) – unit of charge Relationship between charge and distance
1 C of charge (6.25 billion billion) per second
So a wire that carries 5 A has 5 coulombs of charge per second
Electrons flow only when there is a difference in electrical pressure – voltage Higher the pressure (V) stronger the flow
Wires need a pump that provides the voltage to cause flow
Simple Circuit
Have loosely held electrons that travel very easily Most metals
Materials that do not allow electrons to travel freely
Plastic, cloth, glass and dry air