
Instruction Sheet
for the PASCO
Model SE-9788
COIN AND FEATHER TUBE
012-07193A
08/99
$1.00
G
C
E
A
Introduction
The PASCO SE-9788 Coin and Feather Tube
demonstrates the effect due to gravity on objects
falling through a vacuum, compared to the effect on
objects falling through air.
In the demonstration, students see that in an
environment in which air resistance is not
countering the force of gravity (in a vacuum), any
object— regardless of its mass or density—will
require the same time period to reach the bottom of
the tube. However, when air molecules are present,
air resistance counters the force due to gravity.
Students will observe that when air is present,
objects of differing mass or density require
differing time periods to reach the bottom of the
tube.
© 1999 PASCO scientific
F
H
Equipment
INCLUDED
Part Label Part Name
A clear plastic tube
B end piece
C end piece with connector
D “coins”, Styrofoam pieces
E tubing with check valve
F tubing with T and check valve
G 60 cc syringe
H tubing for connection with a
PASCO Pressure Sensor
Note: Parts E, F, and G constitute the vacuum pump
ADDITIONAL SUGGESTED
• ScienceWorkshop Interface (300, 500, 700, or 750)
• Pressure Sensor (CI-6532, CI-6533, or CI-6559)
• computer and data acquisition software
(ScienceWorkshop or DataStudio)
B

Coin and Feather Tube 012-07193A
Basic Setup and Operating Procedure
Note: The first time you set up the Coin and
Feather Tube, you will need to assemble piece F by
attaching the small tube to the T-connector
(Figure 1). (These pieces are left unassembled for
shipping.)
Connect small tube
to T connector here
Figure 1
Assembly of Part F
(once only at first use)
1. Remove an the end piece, put a coin and a feather
or a Styrofoam peanut inside the tube, and replace
the end piece.
Note: Exercise care that your hand or fingers do
not get pinched between the end piece and the
tube.
3. Connect the
vacuum pump to
the Coin and
Feather Tube at
the connecting
piece on end
piece C (Figure
3).
4. Pull a vacuum in
the tube by
pumping the
plunger on the
syringe 50–60
times.
Note: You can
tell approximately
how much air is
being expelled by
the sound coming
from the check
valve.
5. Disconnect piece
E from piece F
(Figure 4) to
remove the vacuum pump.
5
C
10
15
20
25
30
35
40
45
50
55
60
cc
Figure 3
Connecting the vacuum
pump to end piece C
2. Assemble the vacuum pump as shown in Figure 2.
E
G
cc
40
45
50
55
60
Figure 2
Assembly of the vacuum pump
15
10
20
25
30
35
5
E
C
A
F
5
10
15
20
25
30
G
35
40
45
50
55
60
cc
Figure 4
Removing the vacuum pump
F
2

012-07193A Coin and Feather Tube
6. Hold the tube in a horizontal position and then
quickly tip the end with the objects up so the
tube is in a vertical position (Figure 5). Watch
the motion of the objects.
Figure 5
Conducting the demonstration
Setting up with
ScienceWorkshop
1. Connect part H to the hose connector on part A
(Figure 7).
2. Connect part E to part H.
3. Connect part F to part E.
4. Connect the syringe to the T of part F.
5. Connect the Pressure Sensor to the T on part H.
H
C
E
Pressure
Sensor
7. Disconnect piece E from end piece C (Figure 6) to
release the vacuum and repeat Step 6.
E
C
A
Figure 6
Releasing the vacuum
60
55
50
45
40
35
30
25
20
5
15
10
F
A
to
ScienceWorkshop
computer interface
B
cc
G
Note: If vapor forms on the inside wall of the tube
when you release the vacuum, remove an end
piece and allow air to circulate in the tube.
Figure 7
Setting up to measure the pressure inside the tube with a
Pressure Sensor and a
ScienceWorkshop
computer
interface
3

Coin and Feather Tube 012-07193A
Removing a Static Electric Charge from the Inside of
the Tube
A build-up of static electricity on the inside wall of the
tube will cause the Styrofoam peanut to stick to the
tube wall or be impeded in its fall through the
vacuum.
To remove the static electrical charge, humidify the
interior of the tube by putting a damp tissue inside it
and sealing the ends several hours before the
demonstration.
Maintenance
End Pieces
If necessary to achieve a vacuum, you may apply a
small amount of Dow Corning vacuum grease to the
small O-rings on the end pieces. Take care to avoid
getting any of the grease on the inside of the tube
under the end pieces, because the objects inside will
stick to it.
Syringe
• Glycerin may be used on the plunger, but
normally, no lubricant is required.
Caution:
• Do not use any petroleum-based lubricant on the
syringe. The plunger is very intolerant to
petroleum-based substances.
Tube
If you notice any scratches on the inside of the tube
caused by debraiding by the coin, you may want to
switch to a play-money plastic coin.
Safety Considerations
This set is intended to be used by teachers, and
their students while working under appropriate
supervision.
The tube should be used only with the furnished
end pieces. Attempting to evacuate the chamber
while in contact with other surfaces could cause
damage. Severe injury will result from evacuating
the chamber while in contact with skin.
Do not put items in the tube that would be
damaged by, or cause damage as a result of,
reduced pressure. Examples would include sealed
containers, wrist watches, batteries, etc. Certainly
animals should not be placed in the bell jar, for
reasons of law and human decency.
Do not use the apparatus if the bell jar or bottom
plate have become cracked or otherwise damaged.
Limited Warranty
PASCO scientific warrants the 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. The 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.
Address: PASCO scientific
10101 Foothills Blvd.
Roseville, CA 95747-7100
Phone: (916) 786-3800
FAX: (916) 786-8905
e-mail: techsupp@pasco.com
Web site: www.pasco.com
Any liquids entering the pump are apt to be discharged
as a mist or spray. Only safe liquids such as water
should be allowed to be used in association with the
pump, and safety eyeware is definitely required.
The exclamation point within an equilateral
triangle is intended to alert the user of
important operating and safety instructions
that will help prevent damage to the
equipment or injury to the user.
4