PASCO ME-6834 User manual

Instruction Manual
Manual No. 012-07923B
Discover Rotation
Platform
Model No. ME-6834


Instruction Manual
Manual No. 012-07923B
Table of Contents
Equipment List .......................................................... 1
Introduction ............................................................. 2
Basic Operating Procedure ............................................. 2
Rotating on the Stool ..................................................................................................................... 2
Sitting or Laying on the Platform .................................................................................................. 3
Accelerating the Platform with a Rope.......................................................................................... 3
Attaching a Photogate for Motion Measurements......................................................................... 4
Suggested Experiments................................................. 5
Moment of Inertia Experiments..................................................................................................... 5
Torque Experiments ...................................................................................................................... 5
Appendix A: Technical Suppport........................................6

Model No. ME-6834 Discover Rotation Platform
1
!
Discover Rotation Platform
Model No. ME-6834
Equipment List
*Use Replacement Model Numbers to expedite replacement orders.
Included Equipment Replacement
Model Number*
1. Stool 699-128
2. Rotational Platform 003-07900
3. Discover Rotation Platform Manual 012-07923
Additional Equipment Suggested (for experiments) Replacement
Model Number*
PA S C O i n t e r f a c e ( 5 0 0 , 7 5 0 ( S C S I o r U S B ) , U S B l i n k , X p l o r e r, Po w e r L i n k o r
Smart Timer)
CI-6400 or CI-6450 or
CI-7650 or PS-2100 or
PS-2000 or PS-2001 or
ME-8930
Accessory Photogate ME-9204B
Photogate Head ME-9498A
Smart Timer ME-8930
Photogate Port (for use with a USB link, PowerLink, or Xplorer) PS-2123A
Force Sensor (
ScienceWorkshop
®or PASPORT™)CI-6746 or PS-2104
Bicycle Wheel Gyroscope ME-6833
1
2
r=23 cm
h=49 cm
r

Discover Rotation Platform Model No. ME-6834
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Introduction
PASCO’s Discover Rotation Platform is designed to help students
learn the basics of rotational motion and inertia by experiencing
motion themselves. The platform features a stool that can be placed on
the platform for rotational studies with the student sitting. In addition,
the stool can be removed, and students can sit or lay directly on the
platform.
The Accessory Photogate (ME-9420B) or Photogate Head (ME-
9498A) can be used to instrument the Discover Rotation Platform for
measurements of position, velocity, and acceleration. These
measurements can be made in both linear and rotational units. The
photogate must be connected to a Smart Timer (ME-9830),
ScienceWorkshop 500/750 interface, or the PASPORT Photogate Port
(PS-2123) to obtain the above kinematics measurements.
Basic Operating Procedure
Rotating on the Stool
By placing the included stool over the
platform, students can investigate the basics
of rotational motion.
1. Slide the stool over the platform.
2. Fit each leg into a groove on the upper
platform.
Note: The bottom of each leg has a 19 mm
clearance from the ground, so remove
objects that might interfere with the
operation of the stool. For optimal
performance, keep the stool on a hard floor.
The stool may not rotate on carpeting.
3. To rotate, place feet on the foot rungs or extend them out from the
stool (See Figure 1).
Figure 1
Warning: Always
remove any objects that
might interfere with the
rotation of the stool.
Placing objects
underneath the
platform could damage
the platform or cause
injury.

Model No. ME-6834 Discover Rotation Platform
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Sitting or Laying on the Platform
The stool can also be removed so students
can sit or lie directly on the platform for
rotational studies.
1. Have the student sit or lie directly on the
platform (see Figure 2).
2. To study the effects of body position on
rotational inertia, have the student tuck
their arms and legs in or extend them out
while rotating.
Note: For optimal rotation, keep the stool on
a hard floor. The stool may not rotate on
carpeting.
Accelerating the Platform with a Rope
The platform can be accelerated with the push of a hand or the use of a
rope. The rope has the advantage of providing a force at a known
distance from the axis of rotation (torque). This is very useful when
using the expression to investigate rotational motion.
1. Slip one end of the rope between the foot rung and the upper
platform, then wind the desired length of rope in the groove (see
Figures 3a and 3b below).
2. Be sure to pull the rope free when finished applying the torque to
the platform.
Note: It is best to use rope that has minimal stretch. A great way to
measure the force exerted on the platform is to tie the free end of the
rope to a force sensor and pull it to apply the torque (see Figure 4 on
page 4). In all cases, be certain to pull tangent to the platform.
Figure 2
Warning: Without the
stool, students have
nothing to hold onto, so
it is important that
students on the platform
wear clothing that is
not too slick. If
necessary, place a non-
skid pad on the upper
platform to add friction
between the rider and
the platform.
τIα=
Figure 3a Figure 3b

Discover Rotation Platform Model No. ME-6834
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Attaching the Photogate for Motion Measurements
PASCO’s Acce s sory Photoga te (ME-9204B) or Ph otog a te Head (ME-
9498A) can be attached to the bottom platform and used with the built-in
spokes to create a smart pulley.
1. Use the included thumbscrew to attach the Photogate Head to the
bracket on the bottom platform. (See Figures 5a and 5b).
2. Connect the photogate to an interface, such as a 500 or 750
ScienceWorkshop interface.
OR
Connect the PASPORT Photogate Port (PS-2123) to a USB Link or
Xplorer.
3. Students can now measure position, velocity, and acceleration of
the platform and its rider from both linear and rotational frames of
reference.
Figure 4
Figure 5a Figure 5b
Warning: If using the
stool, be sure to tape the
photogate cord to the
floor to avoid
interference with the
stool.

Model No. ME-6834 Discover Rotation Platform
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Suggested Experiments
Moment of Inertia Experiments
Students can both qualitatively and
quantitatively investigate the moment of
inertia with the Discover Rotation Platform.
1. Ask a student to sit on the stool of the
Discover Rotation Platform with 5 kg
masses in each arm (see Figure 6).
2. Have the student sitting on the stool (the
rider) extend his/her arms outward.
3. Have another student (or lab partner) rotate
the rider.
4. After gaining speed, ask the rider to pull the
masses into his/her chest. Qualitatively, the
rider and observers will notice the increase
as the masses are pulled toward the center
axis of rotation.
5. Use a photogate to provide quantitative measurements of position,
velocity, and acceleration.
Using the expression , students can relate the angular acceleration
that results when the masses are moved inward to a decrease in the
moment of inertia of the system.
Torque Experiments
By applying different torques to the platform and using the photogate
to measure the angular acceleration, students can produce a graph to
help them discover the moment of inertia for the system.
1. Attach the Photogate Head to the bottom platform.
Figure 6
τIα=
Figure 7
Warning: Ask students
to tightly grip the
weights with their
hands and fingers. To
avoid injuries, always
enforce appropriate
safety precautions in
the classroom.
Note: For optimal
rotation, keep the
stool on a hard floor.
The stool may not
rotate on carpeting.

Discover Rotation Platform Model No. ME-6834
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Torque Experiments (continued)
2. Wrap a rope or string around the groove of the upper platform (see
Figure 7).
3. Attach a Force Sensor to the rope.
4. Ask one student to sit on the stool.
5. Ask another student to pull the rope to accelerate the rider. Be
certain to pull the rope tangent to the platform.
6. Repeat step 5 two more times, increasing the amount of force
(torque) in each case. A graph with torque on the vertical axis and
angular acceleration on the horizontal axis will produce a slope
equal to the moment of inertia for the system.
7. The experiment could then be repeated with the mass of the system
distributed in a different fashion. For instance, the student could be
tucked in while rotating on the platform in the first experiment and
have arms extended in the second experiment.
Technical Support
For assistance with the ME-6834 Discover Rotation Platform or any
other PASCO products, contact PASCO as follows:
Address: PASCO scientific
10101 Foothills Blvd.
Roseville, CA 95747-7100
Phone: (916) 786-3800
FAX: (916) 786-3292
Web: www.pasco.com
Email: [email protected]
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