PASCO ME-6815 User Manual

Includes

Teacher's Notes

and

Typical

Experiment Results

PROJECTILE CATCHER

Instruction Manual and
Experiment Guide for
the PASCO scientific
Model ME-6815

ACCESSORY

012-05091E

04/00

CATCHER

Instruction Manual and

Experiments Guide for

PASCO scientific

Model ME-6815

© 1993 PASCO scientific $10.00

PROJECTILE

ACCESSORY

PROJECTILE CATCHER

M

ACCESSORY

E

-6
8

1

5

The exclamation point within an equilateral triangle is
intended to alter the user of the presence of important
operating and maintenance (servicing) instructions in
the literature accompanying the appratus.

Projectile Catcher Accessory 012-05091E

Table of Contents

Section Page

Copyright, Warranty, and Equipment Return .................................................... iii

Introduction ........................................................................................................ 1

Equipment .......................................................................................................... 1

Projectile Launcher Setup .................................................................................. 2

Ball Catcher Setup ............................................................................................. 3

Experiments

Experiment 1: Ballistic Pendulum ........................................................ 5

Experiment 2: Conservation of Momentum

in an Inelastic Collision ............................................... 11

Demonstration: Inelastic/Elastic Collisions Demonstration ................. 15

Teacher's Guide ............................................................................................... 19

Technical Support ................................................................... Inside Back Cover

ii

012-05091E Projectile Catcher Accessory

Copyright, Warranty, and Equipment Return

Please—Feel free to duplicate this manual
subject to the copyright restrictions below.

Copyright Notice

The PASCO scientific ME-6815 Projectile Catcher
Accessory manual is copyrighted and all rights
reserved. However, permission is granted to non­profit educational institutions for reproduction of any
part of the manual providing the reproductions are
used only for their laboratories and are not sold for
profit. Reproduction under any other circumstances,
without the written consent of PASCO scientific, is
prohibited.

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.

Equipment Return

Should the product have to be returned to PASCO
scientific for any reason, notify PASCO scientific by
letter, phone, or fax BEFORE returning the product. Upon
notification, the return authorization and shipping instruc­tions will be promptly issued.

➤ ➤

➤ NOTE: NO EQUIPMENT WILL BE

➤ ➤

ACCEPTED FOR RETURN WITHOUT AN
AUTHORIZATION FROM PASCO.

When returning equipment for repair, the units must be
packed properly. Carriers will not accept responsibility for
damage caused by improper packing. To be certain the
unit will not be damaged in shipment, observe the follow­ing rules:

➀ The packing carton must be strong enough for the item

shipped.

➁ Make certain there are at least two inches of packing

material between any point on the apparatus and the
inside walls of the carton.

➂ Make certain that the packing material cannot shift in

the box or become compressed, allowing the
instrument come in contact with the packing carton.

Address: PASCO scientific

10101 Foothills Blvd.

Roseville, CA 95747-7100

Phone: [phone] (toll-free within U.S.)

or

[phone]

FAX: [phone]

email: [e-mail]

web: www.pasco.com

iii

012-05091E Projectile Catcher Accessory

Introduction

The PASCO ME-6815 Projectile Catcher Accessory has
three functions:

• A Projectile Launcher is used to shoot a steel ball into
the ball catcher which is mounted on a Dynamics Cart
to show an inelastic collision.

• The steel ball can be bounced off the rubber bumper of
the ball catcher to show an elastic collision between the
ball and the cart.

• The catcher (without cart) can be suspended from
strings and used with the Projectile Launcher as a bal­listic pendulum.

Equipment

The Projectile Catcher Accessory includes the following:

• a ball catcher

• (2) steel projectile balls

• plate assembly from which to hang the catcher

• spool of thread

• Velcro

®

assembly

steel balls

(2)

support rod

(not included)

rod clamp

support plate

thread

slots for

photogate

timing

PROJECTILE CATCHER

M

ACCESSORY

E-6815

ball catcher

1

Projectile Catcher Accessory 012-05091E

Projectile Launcher Setup

When using the Projectile Catcher Accessory with a
PASCO ME-6800 or ME-6801 Projectile Launcher,
follow these operation guidelines:

1. Please read the General Operations section of the
Projectile Launcher Manual before using the Pro-
jectile Launcher with the Projectile Catcher Acces­sory or any other accessory.

Safety goggles are supplied with the Projectile
Launcher and must be worn when operating the
apparatus.

2. The base of the Projectile Launcher must be
clamped to a sturdy table using the clamp of your
choice. When clamping to the table, it is desirable
to have the label side of the launcher even with
one edge of the table so a plumb bob can be used
to locate the position of the muzzle with respect to
the floor.

3. Mount the Projectile Launcher in a horizontal po­sition, using the two lower slots in the Projectile
Launcher base, as shown in Figure 1.

4. Establish the height at which the Projectile
Launcher should be fired and tighten the thumb­screws as required.

WARNING:

Never look down the
front of the barrel of the Projectile
Launcher because it may be loaded.

To check to see if the ball is in the barrel and
whether the Projectile Launcher is cocked, look
at the slots in the side of the barrel. The yellow
indicator seen through the slot indicates the
position of the piston and the ball can be seen
through these slots when it is in the piston.

Wear safety goggles for eye protection.

0

0

WEAR
SAFETY
GLASSES
WHEN IN USE.

clamp

Projectile

Launcher base

Projectile
Launcher

9

8

7

0

6

0

5

0

4

0

3

0

2

0

LONG

MEDIUM

SHORT

RANGE

1

0

0

ME-6800

Yellow Band in Window

RANGE

RANGE

Indicates Range.

Use 25 mm

CAUTION!

CAUTION!

CAUTION!

DO NOT LOOK

DO NOT LOOK

DO NOT LOOK

DOWN BARREL!

DOWN BARREL!

DOWN THE

balls ONLY!

BARREL.

SHORT RANGE

PROJECTILE LAUNCHER

Launch

Position

of Ball

thumbscrews

table

Figure 1: Projectile Launcher Setup

2

012-05091E Projectile Catcher Accessory

Ball Catcher Setup

Suspending the Ball Catcher as a
Pendulum

Secure the rod clamp on top of the support plate to a
support rod that is clamped to the table. Cut two
pieces of string, each about two meters long. Thread
one string through the front two holes in the ball
catcher. Thread the other string through the back two
holes in the ball catcher. Refer to the diagram below
on how to attach the string. Thread the ends of the
strings through the holes in the support plate and
secure them, making sure the catcher hangs level.

rod clamp

support rod

(not included)

support plate

thread

Velcro Assembly

You may want to quantify and record the results of
your experiments. To enable the user to measure the
height to which the pendulum swings, a thread must
be connected between the ball catcher and the
launcher. The launcher end slips through a Velcro
assembly, and the amount of extension of the string
shows how far the pendulum swung. See Figure 3.

1. Separate the Velcro hook and loop strips.

2. Cut two square pieces of Velcro loop and one
square piece of Velcro hook.

3. Determine the approximate height at which the
Velcro assembly will be applied. This is deter­mined by the approximate height at which the ball
catcher hangs.

4. Remove the protective covering from the back of
each Velcro square.

5. Arrange the two square pieces of Velcro loop and
one square piece of Velcro hook onto the vertical
plate of the Projectile Launcher base as shown.

PROJECTILE CATCHER

M

ACCESSORY

E

-6815

thumbscrew

support plate

string

Figure 2: Suspending the Ball Catcher

Ball Catcher

assembly

washer

6. Cut one piece of Velcro hook 5 – 6 cm long. Do
not remove the protective backing.

7. Tie a thread to one of the front holes in the ball
catcher.

8. The other end of this thread will pass between the
square piece of Velcro hook (attached to the Pro­jectile Launcher base) and the long piece of Velcro
hook, which should be applied to the three Velcro
squares attached to the Projectile Launcher base.

Projectile

thread

Velcro

hook

ball

catcher

assembly

Figure 3: Velcro Assembly

Launcher base

Velcro

loop

3

Projectile Catcher Accessory 012-05091E

Using the Ball Catcher with the
Dynamics Cart

Some experiments require the ball catcher be attached
to the PASCO ME-9430 Dynamics Cart (Plunger
Cart).

3. Activate the Dynamics Cart’s spring plunger trig­ger so the cart plunger catches the front lip of the
ball catcher. See Figure 4.

1. Hook the rear lip of the ball catcher under the rear
end cap of the Dynamics Cart. The spring plunger
on the cart must be in the cocked position. (Note
the orientation of the ball catcher. See Figure 4.)

2. Slip the ball catcher onto the Dynamics Cart. A
hole in the ball catcher should slip over the trigger
of the cart. The tabs on the sides of the ball
Catcher fit on the outside of the cart tray.

rear lip

tray

To remove the ball catcher from the Dynamics Cart,
cock the cart plunger by inserting a pen cap or the
eraser end of a pencil into the hole provided on the
front lip of the ball catcher.

ball catcher

front lip

rear end cap

ball catcher

rear lip

trigger

Dynamics Cart

tabs

Dynamics Cart

plunger

trigger

plunger

Figure 4: Mounting the Ball Catcher to the Dynamics Cart

front lip

4