This document discusses how objects become charged by gaining or losing electrons, and defines positive and negative charges. It explains that like charges repel and opposite charges attract. Methods for charging objects include friction, touch, and induction. The key rules are that charge cannot be created or destroyed, only transferred, and that when two charged objects touch, their total charge is distributed equally between them. Examples are provided to demonstrate calculating the new charges and number of electrons transferred when two charged spheres touch.

2. The study of the effect that charges
in rest have on each other

3. Objects
become
charged by
gaining or
loosing
electrons
Two types charges:
Positive:
Shortage of
Electrons
Negative:
Excess of
Electrons
Protons and
neutrons
cannot be
transferred!!!

4. Forces between charges:
Like charges repel
each other
Opposite charges
attract each other

5. Friction
Electrons are transferred when two
objects are rubbed against each other

6. Touch
Electrons are transferred when a charged
object touches a neutral object

7. Induction (polarization)
Charged particles in a neutral object
rearrange when a charged objects is
brought close to it
Causes temporary charge distribution so
neutral object can be attracted

8. Induction (polarization)

9. Charge cannot be created or
destroyed, but only transferred from
one object to another.

10. -2 nC -4 nC
Charge distribute
equally among both
spheres

11. Calculate new charge on spheres
-2 nC -4 nC
𝑄 𝑓 =
𝑄1 + 𝑄2
2
𝑄 𝑓 =
−2 + (−4)
2
𝑄 𝑓 = −3 𝑛𝐶
-3 nC-3 nC

12. Number of electrons
∆𝑸 = 𝑸 𝒇 − 𝑸𝒊
𝒏 𝒆 =
∆𝑸
𝒒 𝒆
Where ∆𝑄 = Charge Transferred(C)
𝑄𝑖 = Initial Charge (C)
𝑄 𝑓 = Final Charge (C)
𝑛 𝑒 = Number of Electrons
𝑞 𝑒 = Charge of Electron
= −1,6 𝑥 10−19
C

13. Two identical metal spheres have different
charges. Sphere A has a charge of -5 nC.
Sphere B has a charge of 3 nC.
a) What is the nature of the force between A
and B?
b) If the two spheres touched, what will the
new charge on the spheres be?
c) What is the new nature of the forces
between sphere A and sphere B?
d) In which directions were the electrons
transferred?
e) How many electrons were transferred?

14. Two identical metal spheres have different
charges. Sphere A has a charge of
–96 X 10-18 C. Sphere B has 60 excess
electrons.
a) What is the charge on sphere B?
b) If the two spheres touched, what will
the new charge on the spheres be?
c) How many electrons were transferred?