Chapter 23Electric Fields
1. Each of two small non-conducting spheres is charged positively, the combined charge being 40 C.
When the two spheres are 50 cm apart, each sphere is repelled from the other by a force of magnitude
2.0 N. Determ
CHAPTER 7 : MAGNET & MAGNETISM
7.0 MAGNETIC FIELD
A magnetic field is a space around a magnetic material
whereby a body will experience magnetic force.
Magnetic field is a vector quantity and is represented
by B with its unit: Tesla
The direction o
CHAPTER 6: DC CIRCUITS
6.1 The Kirchoffs Rules
a) The junction rule
The sum of the currents entering any junction equals
the sum of currents leaving that junction.
At junction a,
I 1 = I 2 + I4
At junction b,
I 4 +
CHAPTER 8 : INDUCED CURRENT
8.0 Whenever a magnet is moved so that its flux lines cut
across a wire, an emf is induced. Emf depends on:i) the strength of the magnetic field
ii) the rate at which the flux lines are cut
iii) the insertion of magneti
CHAPTER 5 : CURRENT AND RESISTANCE
5.1 The motion of electric charge
Current arises from the motion of electrons.
The electric current I is the rate of flow of charge Q
past a given point P on an electric conductor
CHAPTER 9 : ALTERNATING CURRENT
9.0 Criterion for ac current
a) Current supplied by ac generator
b) Current and voltage change with time
c) Interchanging of the current direction
9.1 The general equation for ac voltage,
(t) = o sin t
(t) = instanti
CHAPTER 4 : CAPACITANCE
A capacitor is an electric component that can store charges.
It consists of two metal plates which is separated by
dielectric (non-conducting) material such as air, paper, mica
etc. A capacitor is named after its dielectric
CHAPTER 3 : ELECTRIC POTENTIAL
3.1 Electric Potential Energy
The potential energy due to a charge placed in an electric
field is equal to the work done against electric forces in
bringing the charge from infinity to the point in question.
CHAPTER 1 :ELECTRIC CHARGE & FIELD
1.1 Static electricity, electric charge & its conservation
All matter is made of atoms. These atoms are made of
electrons, protons and neutrons.
Each proton has one unit of positive charge and each
electron has on