3B Scientific Air Cushion Plate - Handbuch (Seite 87)

Physical Experiments on the Air-Cushion Table
36
Interpretation:
An increase in pressure and a drop in tempera-
ture will transform a gas from the gaseous to the
liquid aggregation state. While the molecules
perform translational movements in the gaseous
state, the prevailing motions in the liquid state
are oscillations, superimposed by few transla-
tions. In the solid state, the lattice elements are
arranged in a regular configuration. They per-
form oscillations around their equilibrium posi-
tion.
2.3.4 Heat Conduction in Solids
Components:
Air-cushion table with fan
Overhead projector
Magnetic barrier, long
2 Pieces
Magnetic barrier, short 2 Pieces
Hover disc, orange 25 Pieces
Model simulation
Real object Model
Space in which the Experiment surface of
behavior of the solid the air-cushion table
is observed
Adjacent lattice
Magnetic barriers
elements
Lattice elements
Hover discs
of the solid
How to proceed:
Align the air-cushion table horizontally and attach
the magnetic barriers. Spread the hover discs
evenly across the experiment surface.
Turn up the fan so that all hover discs are in
motion. Use one finger to set one of the hover
discs located in a corner of the experiment surface
into quick oscillating motions. (Take care to avoid
damage to the experiment surface caused by
friction.) Observe the motions of the hover discs.
Result:
The strong motion of the hover disc is gradually
transferred onto the other ones.The strong motion
of the hover disc is gradually transferred onto the
other ones.
Interpretation:
Energy is transferred by heat conduction in sol-
ids. A rise in temperature at one place of a solid
will increase the mean kinetic energy of the lat-
tice elements at that place. Due to the forces be-
tween the lattice elements, the kinetic energy will
be transferred to the adjacent elements. This caus-
es the temperature to rise also in other places of
the solid body.