Summary Electrostatics Matric 2025

III EE TIEO.BE ITIlIE S
COLOMB'S LAW
like chares repel
Opposite charges attract
DefnTwofree point chargesin free space or air exert a force
on each other This force is directlyproportional to the
product of the charges and inversely proportional to the
square of the distance between the charges
electrostatic
force Charges c
f qq
re Distance between
charges m
Coulomb's constant
9 109 N m C 2

F 9,92

a or q increases the force increases
so long as r is constant

q or q decreases the force decreases
so long as r is constant

Fx're
As r decreases Forceincreases
so long as charges are constant
As r increases Force decreases
so long as changes are constant

, USING COULOMB'S LAW
Convertall chargesto coulombs Phffies symbol conversion
Convertall distances tometers micro
17,4nC 17,4 10 90
102mm 102 10 3m SHE
Newer put sign into the equation
Whenyouget your answer determine the direction based on
like charges repel
Opposites attract


Example
q 92
30cm
9nC 14nC


Determine the force between the charges


EE 50 10 2 0 am

F
KAY
9 109 9 10 9 14 10 9
3
5 ttraction
1,26 10
Force on q 1,26 10 5N attraction right
5
Force on qz 1,26 10 N attraction left