we believe that college students in junior
classes will also find something interesting
in it. The book will also be useful for orga-
nizers of physics study circles, lecturers
taking evening and correspondence courses,
and for teachers conducting extracurricular
activities.
This book would have never been put to-
gether without the inspiration of Acade-mician I.K. Kikoin, who encouraged the
compilation of such a collection of problems.
For many years, Academician Kikoin
headed the central organizing committee
for the all-Union olympiads for schoolchil-
dren and chaired the editorial board of the
journal Kvant (Quant) and the series "Lit-tle Quant Library" The book is a mark of
our respect and a tribute to the memory of
this renowned Soviet scientist.
The authors would like to place on recordtheir gratitude to their senior colleagues in
the olympiad movement. Thanks are due to
V.K. Peterson, G.E. Pustovalov, G.Ya. Mya-
k ishev, A.V. Tkachuk, V.I. Grigor'ev,
and B.B. Bukhovtsev, who helped us in
the formation of our concepts about the
physical problem. We are also indebted to
the members of the jury of recent Moscow
olympiads, who suggested a number of the
problems included. in this book. Finally, it
gives us great pleasure to express our gra-
titude to G.V. Meledin, who read through
the manuscript and made a number of help-
ful remarks and suggestions for improving
both the content and style of the book.