The document explains three methods to charge an object: friction, conduction, and induction. It details how charge is measured in coulombs and describes how objects can become positively or negatively charged through electron transfer. The document also discusses the electrostatic series, which ranks objects based on their ability to gain or lose negative charges.

1. FRICTION,
CONDUCTION AND
INDUCTION

2. How do you charge an object?
• There are three ways to charge an object:
1. Charge by Friction
2. Charge by Conduction
3. Charge by Induction

3. How do you measure “charge”
• The unit of measure for electrical charge is the
Coulomb (C). In equations it is symbolized by a
“q”
• Eg: q = 900C
• One Coulomb is equal to the charge of 6.25 X 1018
electrons (-) or protons (+).
• That is to say, one Coulomb has 6.25 X 1018
electrons.

4. Charging Objects
• Most objects start out electrically neutral, but by
CHARGING an object you create an imbalance in the
number of electrons and protons; the object is then
charged and is either positive or negative.
• You can charge an object through:
• Friction – the transfer of electrons from one object to the other
• Conduction – by having two objects TOUCH each other and
transfer electrons from one object to the next.
• Induction – By inducing electrons to move from one object to the
other.

5. Charging by Friction
• When two neutral objects are rubbed against each other,
one object may pull electrons away from the other
creating one positive object and one negative object.

6. Electrostatic Series:
 All objects begin neutral & can become
positively or negatively charged
 A positively charged object has more
positives than negatives
 A negatively charged object has more
negatives than positives

7. • Electrostatic series is a list that ranks objects’
ability to take negative charges
Electrostatic Series:
Rubber
Ebonite
Polyethylene
Cotton
Silk
Wool
Glass
Acetate
Fur / Hair
Items at top
take negatives
Items at bottom
lose negatives

8. Your cat rubs against a rubber balloon. What will
be the charge on the balloon? Your cat’s fur?
Rubber
Ebonite
Polyethylene
Cotton
Silk
Wool
Glass
Acetate
Fur / Hair
Rubber
Fur / Hair
Items at top
take negatives
Negatives
Rubber
balloon
becomes
negative
Cat’s fur
becomes
positive

9. In a lab, you take a piece of neutral wool & neutral
polyethylene & rub them together. What will be their
charges?
Rubber
Ebonite
Polyethylene
Cotton
Silk
Wool
Glass
Acetate
Fur / Hair
Wool
Polyethylene
Items at top
take negatives
Negatives
Polyethylene
balloon
becomes
negative
Wool
becomes
positive

10. In a lab, you rub a piece of cotton &
ebonite together. Then you rub a piece
of silk & wool together.
Rubber
Ebonite
Polyethylene
Cotton
Silk
Wool
Glass
Acetate
Fur / Hair
Cotton is +
Silk is -
They
would
ATTRACT
You then bring the charged piece of
cotton & the charged piece of silk
together. What will happen?
+
-
-
+

11. You rub your hair with a balloon.
Explain using words & pictures, why
your hair “sticks up”.
1st Hair & balloon are
both neutral
2nd Rubber balloon takes
negative charges from the
hair. So, balloon becomes
negatively charged & hair
becomes positively charged
3rd Since hair is positive &
like charges repel,
hair sticks up!!!
+
+
++
+
_ _
_
_
_

12. Charging by Conduction
• An object can be charged by touching it with another
object that already has a charge. The resulting object will
then have the same charge but weaker in strength than
the original object.

13. Charging by Conduction
• This image shows how a positive charged object
alters the charge on the globe via conduction.

14. Charging by Conduction
• This image shows how a negative charged object
alters the charge on the globe via conduction

15. Charging by Induction
• Objects do not touch (one is charged, one is neutral)
• Proximity of the charged object causes (induces) the
charges in the neutral object to separate.

16. Charging by Induction
• This image shows how a negative charged object
alters the charge on the globe via induction.

17. Charging by Induction
• This image shows how a positive charged object
alters the charge on the globe via induction.

18. • Two types of charges – positive (+) &
negative (-)
• “Opposites Attract”
• “Like Repel”
• Items at the top of the electrostatic series
list take negative charges
• Only negative charges move
• Three methods to charge an object:
friction, conduction, induction. These three
methods are what cause static
electricity.