Atoms contain charged particles called
protons and electrons
What happens when two electrons/protons come close together?
They repel each other
What happens if a proton and electron come close together?
They attract each other
Why do protons attracted electrons?
Because the two have opposite electric charges
What is the charge on a proton?
Positive
What is the charge on an electron?
Negative
How do charges interact?
Charges that are the same repel each other. Charges that are different attract each other.
What is the interaction between electric charges called?
electricity
Electric force
The force between charged objects
What is a gravitational field?
The space around an object where the objects gravitational force is exerted
A ___________ _____________ extends around a charge objects
Electric field
Electric field
a region around a charged object where the object's electric force is exerted on other charged objects
Electric fields and forces get weaker ...
The farther away they are from the charge
An electric field is _____________.
Invisible
What do you use to represent electric fields?
Field lines
What does a field line show?
The force that would be exerted on a positive charge at any point along that line
Positive charges are __________________ by positive charge and ______________ to negative charges.
Repeled, attracted
Field lines point away from __________ charges and toward ___________ charges.
Positive, negative
Why do single charges have straight field lines ?
Since a positive will be repeled away from or attracted to it in a straight line
When multiple charges are present ...
Each charge exerts a force
What do the forces on the field line combine to make?
A more complicated field line
Most object have ___________ ___________ charge
No overall
An atom usually has as many electrons as it does protons ...
So each positive charge is balanced by a negative charge
Atoms are uncharged or ___________
Neutral
How does an uncharged object become charged?
By gaining or losing electrons
When does an object have an overall positive charge?
When an object loses electrons because it is left with more protons than electrons
When does an object have an overall negative charge?
When it gains an electron
static electricity
The buildup of electric charges on an object
What happens in static electricity?
charges build up on an object, but they do not flow continuously
Charges are neither ________ nor _________.
created, destroyed
Law of Conservation of Change
states that charges are neither created nor destroyed
An object ___ become charged by destroying or creating its own electrons.
can't
if one object loses electrons,
another object must pick them up
There are four methods by which charges can redistribute themselves to build up static electricity:
By friction, by conduction, by induction, and by polarization
When two uncharged objects are ____________, some electrons from one object can move onto the other object.
rubbed together
When an object gains an electron what happens?
It becomes negatively charged
When an object looses an electron what happens?
It becomes positively charged
Charging by _________ is the transfer of electrons from one uncharged object to another by rubbing the objects together.
Friction
when a charged object touches another object,
electrons can be transferred
Charging by conduction
the transfer of electrons from one object to another by direct contact
Electrons transfer from the object that has more ______________ charge to the object that has more _______________ charge.
Negative, positive
Electrons can react to the electric field of a charged object ________ touching the object itself.
without
What are some examples of materials that electrons can easily leave their atoms?
metals
When a metal object is close to a negatively charged object, electrons are __________ by the field and move away from it.
Repelled
The close end of the metal object becomes ________ charged
positively
The far end of the metal object becomes _______ charged
negatively
Induction
A method of redistributing the charge on an object by means of the electric field of another object; the objects have no direct contact.
Polarization
The process through which electrons are attracted to or repelled by an external electric field, causing the electrons to move within their own atoms
Charges don't transfer between object in __________________ or ____________, so neither method changes the overall charge of objects.
Polarization, induction
In induction and polarization,
parts of objects end up charged in opposite ways
Positvely charged objects gradually ________electrons from the air.
gain
Negatively charged objects gradually __________electrons to the air.
lose
T/F: Objects eventually become neutral again.
True
static discharge
The loss of static electricity as electric charges transfer from one object to another
Static discharge can be thought of as?
the movement of electrons
Why does static discharge often produce a spark?
moving electrons can heat the air around the path until glows.
What type of air condition do objects hold on to charge better?
Dry air
Why don't particles stay charged as long in humid weather?
bc water collects on the surfaces of objects , and the water picks up charge from the objects
Lighting bolts are an example of ______________ ___________.
static discharge
Negative charges at the bottom of storm clouds create _____ ______.
electric fields
How does lightning travel?
from negative to positive