Charges in an electric field
Field inside conductors
Conductors contain a lot of free moving charges, so that if a
piece of conductor is placed in an electric field, the charges start
moving. But they cannot move forever, they must eventually
redistribute

Wave motion
What is a wave?
Wave is a propagation of a disturbance of matter
This is a still picture of a disturbance. The points on the spring are oscillating in
the vertical direction. At the next instance a point at any given point will
assume the valu

Refraction and lenses
Law of Refraction & Fermats Principle
Angle of refraction is determined by relative velocities of light in two media. The latter
can be characterized by refractive indexes
A
n1 sin 1 n2 sin 2
n1
c
c
sin 1 sin 2
v1
v2
n2
D
B
K
C
ABn1

Diffraction
Single-slit diffraction: minima
Diffraction pattern is characterized by a bright central maximum of intensity and a
sequence of weaker maxima separated from each other and the central maximum by
minima of intensity. Positions of the minima are

Inductance and ac circuits
Mutual inductance
When two circuits are nearby, the current in
one circuit creates a magnetic field, which is
not zero along the area occupied by the
second circuit. This field, therefore, creates
magnetic flux through the secon

Magnetic Induction
Magnetic field and currents: new relationship
A current creates the magnetic field (Biot-Savart law)
Can the magnetic field create a current?
A constant (in time) magnetic field cannot create a
current in a stationary wire loop.
Cha

Electric charges and interaction
between them
New properties of matter
Electrical charges
Simple experiments, in which two different materials are rubbed with a silk cloth
demonstrate different behavior: two hard rubber rods repel each other, two plastic

Electric current and DC
circuits
Moving charges: what is different?
In the case of charges moving through conductor, all of our
conclusions about charge distribution in it lose their validity:
Electric field in the bulk of conductors with moving charges

The Magnetic field
A new kind of force
Natural magnets and magnetic field
Simple empirical facts:
1. Certain minerals attract metal pieces
2. A needle laid next to a natural magnet orients itself along lines passing
through points called poles of a magnet

Electric Potential
Work by Electrostatic Forces
Work and potential energy
Coulomb force is a conservative force, which means that if a
charge moves from point 1 to point 2 the work of the Coulomb
force does not depend on the path and can be described in
t

Capacitance
Storing electrostatic energy
Potential energy of the system of conductors
If a charged object is a conductor, formula
1
U QV
2
is valid for a conductor of an arbitrary shape. Since potential is only defined
with respect to a particular zero le

Gausss law
Closed surfaces and the field lines
The idea of the density of field lines can be quantified by using closed
surfaces. Closed surfaces divide space into two distinct regions: One
inside the surface, and the other one outside.
Consider such a su

Foundation of Geometric Optics
Rays and ray propagation
Ray model of light is based on an assumption
that light propagates along straight lines unless
its propagation is obstructed by obstacles.
According to this model, each point of a light
source emits