PREFACE
The student of physics at the senior college or early graduate
'
level is confronted with a vast array of physical concepts, interpretative theories and experimental techniques, all of Whichhave
expanded rapidly in recent years.
In addition to an extension of
the earlier knowledge of alpha, beta, gamma, cosmic and X—rays,
electrons, protons, photons, gas-lled and vacuum tubes, photoelectric effects, radioactivity, etc., new entities such as the positron
and neutron. have been discovered.
The development of magnicent devices for the acceleration of elementary particles to high
‘
energies, as well as the use of projectiles from radioactive sub—
stances, has opened the door to the transmutation of elements and
to a fuller knowledge of the nature of the nucleus of the atom.
Radioactive substances have been produced by articial means.
The underlying purpose of this book is to present the experimental evidence for those concepts which
in the domain of
electron cmd nuclear physics.
Simple statements of the experi—'
'
mental facts and physical principles of both the «newer and
concepts are recognized as being of great help in bridging the gap
between the early study of physics and the specialization of
advanced research.
'
'
A strenuous effort has been made to develop the subjects in
such a sequence as to avoid reference at any point to discussions
which appear later in the book. The early chapters treat of the
electron, its charge, mass, wave—length and emission from hot and
u
_cold surfaces.
These are followed by Chapters dealing with elec—
'
trical phenomena specic to the outer parts” of theatom. In suc—
ceeding chapters there are discussions of the phenomena inVolving'
the nuclei of atoms, such as positive rays, natural
articial
-
.
radioactivitÿ, transmutations, etc. This large amount of m‘ate—
rial has been;presented in one book, because many basicrèlati0nS
and experimental techniques are common to several of these elds
,
of study. '
'
‘
’
'_
w
'
"
At the end of each chapter there is a
-—
'
'
experiments, by means of
is brought tforecog—
_
‘
».
111
*
’
,
The student of physics at the senior college or early graduate
'
level is confronted with a vast array of physical concepts, interpretative theories and experimental techniques, all of Whichhave
expanded rapidly in recent years.
In addition to an extension of
the earlier knowledge of alpha, beta, gamma, cosmic and X—rays,
electrons, protons, photons, gas-lled and vacuum tubes, photoelectric effects, radioactivity, etc., new entities such as the positron
and neutron. have been discovered.
The development of magnicent devices for the acceleration of elementary particles to high
‘
energies, as well as the use of projectiles from radioactive sub—
stances, has opened the door to the transmutation of elements and
to a fuller knowledge of the nature of the nucleus of the atom.
Radioactive substances have been produced by articial means.
The underlying purpose of this book is to present the experimental evidence for those concepts which
in the domain of
electron cmd nuclear physics.
Simple statements of the experi—'
'
mental facts and physical principles of both the «newer and
concepts are recognized as being of great help in bridging the gap
between the early study of physics and the specialization of
advanced research.
'
'
A strenuous effort has been made to develop the subjects in
such a sequence as to avoid reference at any point to discussions
which appear later in the book. The early chapters treat of the
electron, its charge, mass, wave—length and emission from hot and
u
_cold surfaces.
These are followed by Chapters dealing with elec—
'
trical phenomena specic to the outer parts” of theatom. In suc—
ceeding chapters there are discussions of the phenomena inVolving'
the nuclei of atoms, such as positive rays, natural
articial
-
.
radioactivitÿ, transmutations, etc. This large amount of m‘ate—
rial has been;presented in one book, because many basicrèlati0nS
and experimental techniques are common to several of these elds
,
of study. '
'
‘
’
'_
w
'
"
At the end of each chapter there is a
-—
'
'
experiments, by means of
is brought tforecog—
_
‘
».
111
*
’
,