New trends in physics teaching, v.4; The ... - unesdoc - Unesco

New Trends in Physics Teaching IV
The problem of energy in the physics course in Soviet
modern secondary schools
G.A. MESYATS AND Y.B. YANKELEVITCH
In the modern Soviet secondary school physics is taught in forms 6 to 10 (five years in all, the
total number of class-hours amounting to 550). The teaching pre-supposes two stages of study:
at the first stage (6th and 7th forms - 150 hours), pupils acquire a simple knowledge of the
basic laws of mechanics, molecular physics, electromagnetism, atomic physics. At the second
stage (8th, 9th, 10th forms - 400 hours), schoolchildren make a more detailed study of all
parts of physics, including optics, oscillations and waves, nuclear physics.
The problems of energy are dealt with at both stages and in almost all parts of physics.
When studying mechanics at the first stage, the schoolchildren get the first notion about
energy as a ‘physical value which shows what amount of work a body can perform’. They consider
kinetic and potential energies and the transformation of one kind of energy into another.
The explanations of such notions as internal energy (‘kinetic energy of heat movement and
potential energy of the interaction of molcules of a body’) and temperature of a body are
illustrated by examples. Processes causing changes of the internal energy are also considered.
When heat phenomena are studied, much attention is paid to the laws of conservation and
transformation of energy in mechanical and heat processes. We focus on the energy of the Sun
which is flowing continually to the Earth and being absorbed by it. This theme facilitates a better
understanding of the laws of conservation and transformation of different kinds of energy,
helping the pupils to make vivid evaluations.
The second stage of studying physics starts in the 8th form where, in the mechanics course
(kinematics, dynamics, laws of conservation in mechanics), mechanical work and energy and the
laws of conservation of energy are deeply and thoroughly analyzed.
In the 9th form, children study molecular physics and thermodynamics (special attention here
is paid to the energy of a perfect gas and the thermodynamic laws of energy conservation). In the
section on electrodynamics and electromagnetism the energies of a charged body, of a capacitor
and of the magnetic field are considered.
In the 10th form, oscillations and waves are studied deeply. The transformation of one kind
of energy into another is illustrated by harmonic oscillations (kinetic-potential). The study of
104