PASCO WA-9607 User Manual

Instruction Sheet
for the PASCO
Model WA-9607

012-03283D

10/95
$1.00

Chladni Plates Kit

Typical Pattern

Square Chladni Plate

Important for SF-9324:

Push to Lock position when not in

use or when changing plates.

Wave Driver

(not included)

Introduction

Typical Pattern

Circular Chladni Plate

Sand along typical

nodal lines of standing

wave pattern

Banana plug

fits in drive shaft

Sand

Sand

Shaker

A string vibrating at a resonant frequency develops a
standing wave pattern consisting of regularly spaced
nodes (points on the string that do not vibrate) and
antinodes (points where the amplitude of vibration is a
maximum). More interesting standing wave patterns are
created with vibrations in media that support wave
propagation in two dimensions, such as a metal plate or a
drum head.

In the early nineteenth century, Ernst Chladni (pro­nounced Klädne) developed a technique for investigating
two dimensional wave patterns. Sand is sprinkled onto a
plate, and a violin bow is used to vibrate the plate. The
sand comes to rest on the nodal lines, where no vibration
occurs. Sand that is not resting on a nodal line gets
bounced around until it finally lands on a nodal line and
comes to rest.

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Phone [phone] • FAX [phone] • email: [e-mail]

When used with the PASCO Model WA-9753 Wave
Driver II or SF-9324 Mechanical Wave Driver, the
Chladni Plates Kit improves on Chladni's original
method, allowing you to produce steady plate vibra­tions at any desired frequency. The illustrations at the
top of the page show examples of the nodal patterns
that can be created.

Equipment

The Model WA-9607 Chladni Plates Kit includes:

• Square Chladni Plate (24 cm sides)

• Circular Chladni Plate (24 cm diameter)

• Sand, extra fine (1 kg)

• Sand Shaker

better

ways to

teach science

Chladni Plates Kit

012 - 03283D

➤ NOTE: The Chladni Plates Kit is designed to
be used with the PASCO Wave Drivers (WA-9753
or SF-9324). The banana plug connectors attached
to the plates connect directly with the drive shaft.

➤ IMPORTANT: Always lock the drive shaft of
the SF-9324 before attaching or removing the plates.

To Use the Chladni Plates

➀ Connect the Chladni plate to the drive shaft as illus-

trated on the previous page. The banana plug mates
directly with the hole in the drive shaft.

➁ Sprinkle sand on top of the plate.
➂ Unlock the drive shaft of the Wave Driver.
➃ Connect the Wave Driver to your function generator/

amplifier (such as PASCO Models PI-9587C Digital
Function Generator or PI-9598 Student Function Gen­erator). Vibrate the plate over a range of frequencies
from about 100 Hz up to 5 kHz. As you slowly vary
the frequency of vibration, you will discover a variety
of standing wave patterns. (Don't change the fre­quency too fast—the resonances are very sharp and
you might miss some.) Adjust the amplitude and the
amount of sand as necessary to get clear patterns.

➄ An interesting experiment is to hold an edge of the

plate to determine the effect on the resonant frequen­cies and patterns. You can induce asymmetric stand­ing wave patterns in the round plate by unscrewing the
banana plug and connecting it to the off-center hole in
the plate.

➅ For further investigations, you may want to create

your own Chladni plates. We recommend you cut
them from aluminum sheets (approx. 0.035"), but you
might find it interesting to experiment with other ma­terials.

Keeping It Quiet

At high frequencies, you’ll find that the Chladni plates
and the wave driver are LOUD. You can minimize the
noise with the optional WA-9610 Chladni Plate Cover, a
clear acrylic cover that fits over the plates and driver.

Optional WA-9610 Chladni Plate Cover

Limited Warranty

PASCO scientific warrants this product to be free from
defects in materials and workmanship for a period of one
year from the date of shipment to the customer. PASCO
will repair or replace, at its option, any part of the product
which is deemed to be defective in material or workman­ship. This warranty does not cover damage to the product
caused by abuse or improper use. Determination of
whether a product failure is the result of a manufacturing
defect or improper use by the customer shall be made
solely by PASCO scientific. Responsibility for the return
of equipment for warranty repair belongs to the cus­tomer. Equipment must be properly packed to prevent
damage and shipped postage or freight prepaid. (Dam­age caused by improper packing of the equipment for
return shipment will not be covered by the warranty.)
Shipping costs for returning the equipment, after repair,
will be paid by PASCO scientific.

To Reach PASCO

For Technical Support call us at 1-800-772-8700 (toll­free within the U.S.) or [phone].

email: [e-mail]
Tech support fax: [phone]

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