Bài giảng Vật lý đại cương 2 - Chương 1: Thuyết động học phân tử chất khí trình bày phương trình cơ bản và các hệ quả, nội năng khí lý tưởng, định luật phân bố đều năng lượng theo bậc tự do, công thức khí áp, phân bố Boltzman, quãng đường tự do trung bình của phân tử, các hiện tượng vận chuyển.
Học thuyết về ánh sáng là một trong những học thuyết quan trọng của vật lý
hiện đại. Học thuyết này dựa trên quan niệm về lưỡng tính sóng - hạt của ánh
sáng. Quang học trong chương trình bậc trung học phổ thông hiện nay thường
được chia thành hai phần: quang hình học và quang lý.
Many physical phenomena of great practical interest to engineers
chemists, biologists, physicists, etc. were not in Gen. Phys. I & II
The development of experimental equiment and techniques
modern physics can go inside the microscopic world (atoms,
electrons, nucleus, etc.)
New principles, new laws for the microscopic (subatomic)
world were discoverved
We knew that the concepts of mechanical work and energy play an
important role in studying mechanical phenomena.
Concerning to thermal phenomena, there exits a new form of energy
Heat can be transferred from one to other systems
For a system with volume held constant, the effect of heat is to
change the temparature of a system.
The first law of thermodynamics gives the quantiative relations between
the internal energy of a system and the quantities of heat and work that
the system exchange with surroundings. It express the conservation of
The first law of thermodynamics is true, but not enough ! Why ?
Many thermodynamic processes which don’t violate the 1st
but don’t happen in nature !
1.1 Induction experiment:
Inside the shaded region, there is a
magnetic field into the board.
– If the loop is stationary, the
Lorentz force (on the electrons in
the wire) predicts:
(a) A Clockwise Current; (b) A Counterclockwise Current; (c) No Current
Now the loop is pulled to the right at a velocity v.
– The Lorentz force will now give rise to:
1.1 The balance of charges on conductors:
In conductors there are charged particles which can be freely
move under any small force. Therefore the balance of charges on
conductors can be observed under these circumstances:
The electric field equals zero everywhere inside the conductor
E = 0
The electric potential is constant inside the conductor
V = const
The electric field vector on the surface of conductors direct along the
normal of the surface at each point
E = En
The surface of conductors is equipotential
Inside conductors there is no charge.
We have known the close connection between changing eletric fields
and magnetic fields. They can create each other and form a system of
Electromagnetic fields can propagate in the space (vacuum or material
environment). We call them electromagnetic waves. They play a very
important role in science and technology.
To have a quantum-mechanical treatment we model a crystalline solid as
matter in which the atoms have long-range order, that is a recurring
(periodical) pattern of atomic positions that extends over many atoms.
We will describe the wavefunctions and energy levels of electrons in
such periodical atomic structures.
We want to answer the question: Why do some solids conduct curr
We want to answer the question: Why do some solids conduct current ent
and others don and others don’ ’t? t?...
It has been known from the previous chapter that light, and in general,
electromagnetic waves have particle behavior. Some latter time than the quantum theory of light, it was discovered
that particles show also wavelike behavior.
The wave-particle duality of matter is the fundamental concept of
Newton’s classical physics should be replaced by the new mechanics
which is able to describe the wave nature of particles
“Diffraction” of light can be understood as any deviation of light rays
from their geometrical propagation line (that is straight in a homogeneuos material)
An example (shown in the picture):The edge of shadow is never
perfectly sharp. Some light
appears in the geometrical
shadow, and there are dark
and light fringers in the area of
Investigation of the magnetic properties of materials is very important,
because magnetic phenomena have various scientific and technical
The macroscopic properties of matter are a manifestation of the
microscopic properties of the atoms of which it is composed.
The magnetic properties of materials may be very different for types of
material, depending on their nature and structure.
At the end of the 19-th century, physics was at its most confidence
situation. Classical phyics, as formulated in Newton’s law of mechanics
and Maxwell’s theory of electromagnetism, have proved very successful
in solving every problem.
→At that time there seemed to be no question for which physics could
not provide an answer !!!
But then it came as a great shock when some simple phenomena were
observed which could not be explained by classical physics
→a new theory, quantum theory, was developed at the beginning of the
Magnetic effects from natural magnets have been known for a long
time. Recorded observations from the Greeks more than 2500 years
The word magnetism comes from the Greek word for a certain type of
stone (lodestone) containing iron oxide found in Magnesia, a district in
Properties of lodestones: could exert forces on similar stones and
could impart this property (magnetize) to a piece of iron it touched.
Interference and diffraction of light are arguments for wave
charactiristics of light.
We know that there are two types of wave processes: transverse &
longitutional waves →to what are light waves belong ?
Study of polarization of light makes clear that
This conclusion is in according to the concept that light waves are
electromagnetic waves with a definte band of frequencies. Recall that
electromagnetic waves are transervse waves in which e-vectors &
m-vectors oscillate in such follwing directions...
• Imagine an atom with excess energy. Without external action,
the atom would, after a period of time, spontaneously emit light,
whose properties (e.g. its direction) are random — only the
energy is fixed.
• This situation changes when the
atom is shone with a light wave of
the corresponding energy. There
is then a higher probability that
the atom will also simply copy the
remaining properties of the incident
wave: It then emits light that is
in step with the original and
propagates in the same direction....
We have known how can describe the electric field in vacuum.
How is the electric field in a matter environment?
In this chapter we consider the case that the environment is a
Recall that in a conducting body (conductor) the charges move freely in
respond to an electric field, but in nonconducting bodies the charges can
not move freely.
Nonconducting bodies are called dielectrics or insulators.
From this Chapter we will study thermal properties of matter, that is
what means the terms “hot” or “cold”, what is the difference between
“heat” and “temparature”, and the laws relative to these concepts.
We will know that the thermal phenomena are determined by internal
motions of molecules inside a matter. There exists a form of energy
which is called thermal energy, or “heat”, which is the total energy of
all molecular motions, or internal energy.
It is well known for you that every atom contains as its center
a nucleus that is:
much smaller in size than the atom
carrying almost the total mass of the atom
This chapter provides deeper knowledge about NUCLEI
Trong chương trình đào tạo đại học của các ngành liên quan đến sinh học, Học phần Sinh lý học người và động vật, được xem là học phần cơ sở của nhiều ngành đào tạo như: Chăn nuôi, Thú y, Động vật học, Sinh học, Sư phạm kỹ thuật Nông lâm, Cử nhân điều dưỡng, Bác sỹ đa khoa, …