3 structure and properties of solids – 3B Scientific Air Cushion Plate User Manual
Page 33

Physical Experiments on the Air-Cushion Table
34
2.3
Structure and Properties of Solids
Interpretation:
The lattice elements in a solid are arranged in a
regular configuration. They perform irregular
oscillations around their equilibrium position.
The amplitudes vary from location to location and
change with time. A drop in temperature makes
the mean kinetic energy of the oscillating lattice
elements decrease.
Note:
To provide a proper demonstration of the drop in
temperature it is recommended to turn the fan
down as far as possible during the experiment.
This experiment can also be demonstrated using
red or green discs. It will be necessary, however,
to reduce the effective experiment surface by
shifting barrier no. 2 to the middle of the air-
cushion table.
2.3.2
Melting a Solid
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.
Adjust the airflow strong enough so that all hover
discs are sure to float even when the impulse valve
is opened.
Open the impulse valve several times at an
interval of several seconds and observe the
motion of the hover discs.
2.3.1
Configuration and Motions of the
Lattice Elements in a Solid
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, attach
the magnetic barriers and spread the hover discs
evenly across the experiment surface. Adjust the
airflow strong enough so that the hover discs are
sure to float even when the impulse valve is
opened. Observe the motion of the hover discs
after opening the impulse valve once.
Result:
Each hover disc is bound to a specific location. It
performs oscillating and circular motions around
its equilibrium position. The amplitudes vary and
are constantly changing. The mean kinetic energy
of the hover discs gradually decreases.