The Impractical Mousetrap Alert

The Impractical Mousetrap Alert: An Adventure into the Superfluous

Team A2-4 David Otten Michael May Alexander Mavrommatis THE IMA...... 3 DESIGNING THE DREAM...... 3 THE PHYSICAL BUILD...... 4

SUPPORTING THE GIANT...... 4 A STRONG ARM...... 4 TRACK AND FIELD...... 4 CHIMES AWAY...... 5 ENERGY CONVERSIONS AND EFFICIENCY...... 5

CONVERSION POINTS...... 5 EFFICIENCY CALCULATIONS...... 5 BILL OF MATERIALS...... 6 CONCLUSIONS...... 7 RESOURCES...... 8

2 The IMA The Impractical Mousetrap Alert (IMA) system is powered by the mousetrap itself. The device was designed to alert the user by way of chiming when the trap springs and catches vermin. The IMA utilizes a twelve inch arm that swings two hundred and seventy degrees when the trap activates. At the end of its arc, the arm collides with a golf ball, sending it down a track of sorts, where it bumps into the user-mounted wind chimes and activates the chiming sound. This device tastefully allows victims of vermin invaders to discreetly remove the vermin, saving the embarrassment and surprise that come with more traditional mouse- trapping devices.

Designing the Dream In the beginning, it was decided that team A2-4 would design a machine that was powered by a mousetrap and involved a rolling ball. These were the only criteria, and left the rest to the imagination. The design process of the IMA was quick, but not without its changes. The original plan called for a more intricate construction, dealing with a light bulb and dangerous wiring. In this design, a metal ball bearing would roll down the track instead of the golf ball, and complete an electrical circuit that would light the twelve volt battery- powered light bulb. Unfortunately, this idea became too complex for the time allotted, and was promptly scrapped. The second design of the IMA implemented a bell in the place of the light bulb, offering a much easier and more practical solution. In addition to the bulb replacement, the metal ball bearing was abandoned in favor of a golf ball, as they are far more common in the average household, and less likely to cause bodily harm to the irresponsible. To the dismay of the Rube-Goldberg community, this idea, however ingenious, was not possible. The reason is very simple: bells are not available for purchase at most vendors during the bell off-season1. This painful discovery was made after an hour-long hunt. The third and final design leaves the basics of the first two intact, and has become the IMA known and loved by the public. The same structure is used, however instead of a light bulb or bell, wind chimes are the preferred method of kinetic-to-sound energy transfer.

1 Winter is the prime season for bell sales, thus spring and summer are usually skipped by bell sellers

3 The Physical Build

Supporting the Giant The IMA in its finished form consists of a wooden base with two large wooden supports extending vertically. The supports provide a strong point to which another diagonal support, the swinging arm, and the ball track can be attached. (Fig.1)

Figure 1

A Strong Arm The swinging arm attached to the supports is twelve inches long, and is activated by way of a standard mousetrap nailed to the diagonal support. (Fig. 1)

Track and Field The golf ball track is twelve inches above the base of the IMA, attached to the main supports. It allows the golf ball to travel a straight line towards the wind chimes. (Fig. 2)

Figure 2

4 Chimes Away The chimes themselves are attached to the diagonal support, allowing the ball to strike readily and easily. (Fig. 2) Energy Conversions and Efficiency This section of the report includes all energy conversion points and calculations.

Conversion points Starting point: The mouse trap springs with 9N of force, converting potential energy to kinetic energy. 1. 9N of force is transferred from the mouse trap to the swinging arm in the form of kinetic energy. PE  KE 2. The arm swings a 270˚ arc, hitting the golf ball. Through this collision, the kinetic energy of the arm passes to the ball. KEKE 3. The kinetic energy of the arm moves to the ball, converting the ball’s potential energy into kinetic energy, adding to the original energy gained from the arm. KEPE+KE 4. The ball rolls down the track and collides with the wind chimes. This transfers some of the ball’s kinetic energy to the chimes, which in turn convert that energy to sound energy. KESE 5. The ball hits the end of the track, losing all kinetic energy as sound, heat, etc. KE(various other types of energy)

Efficiency Calculations 1. Velocity of the arm after the mousetrap springs 2 2 v 2 m m 9N = (.037kg)  v  75.4  vi  8.507 .310 s 2 s 2. Velocity of the ball after the arm hits m m m (.037kg)(8.857 )  (.0459kg)(0 )  (.037kg)(0 )  (.0459kg)v' s s s b m m (.037kg)(.8.857 )  (.0459kg)v'  v'  7.14 s b b s m 7.14 Efficiency  s  .806  80.6% m 8.857 s

5 3. Velocity of the ball when it hits the chimes m m m (.310m)(9.81 )(.0459kg)  .5(7.14 ) 2 (.0459kg)  .5(.0459)(v ) 2  (.1524m)(9.81 )(.0459kg) s 2 s 2 s 2 2 2 m m v  54.07  v2  54.07  7.35 2 s 2 s 4. Velocity of the ball when it hits the end of the track m m m (.310m)(9.81 )(.0459kg)  .5(7.14 ) 2 (.0459kg)  .5(.0459)(v ) 2  (0m)(9.81 )(.0459kg) s 2 s 2 s 2 2 2 m m v  57 v2  57  7.55 2 s 2 s 5. Conservation efficiency

Workout Workin  9N(.05m)  1.41N  m Workin m Work  .5(.0459kg)(7.55 ) 2 (.01m)  1.31N  m out s 1.31N  m  .929  92.9% 1.41N  m

This means that the IMA lost only 7.1% of its energy during its function from when the mouse trap triggered to when the ball hit the end of the track!

Bill of Materials  Dowel Rod…………………………………………………………….$1.99  Molding………………………………………………………………..$3.49  Mouse Trap…………………………………………………………….$1.49  Wind Chime…………………………………………………………....$1.63  Fasteners……………………………………………………………….$0.60  Screw Eye……………………………………………………………...$3.29  Graphite Lubricant……………………………………………………..$1.79  Contact Glue…………………………………………………………...$3.99 Total: $18.27

6 Conclusions As a final build, the IMA has an infinite repeatability, so long as all parts are in working order. Our machine proves to be a simple yet roundabout way to accomplish a simple task: to activate wind chimes. The IMA was a successful endeavor, needing no changes whatsoever save some louder chimes. During the production of the IMA, we learned how to work cohesively, produce results efficiently, and apply our knowledge of conceptual physics to real-world situations. The hardest part of the IMA outside of its actual construction was finding appropriate equations for each energy transfer. Also, having no instruments to test our calculations, we are left relying on our own mathematical abilities to determine actual specifications and efficiencies. Although our mathematical skills in this respect are not lacking, real-world analysis would have been very helpful for verification purposes. Given more time and resources, we would have utilized a broader array of parts, perhaps implementing some of the more complicated elements of our earlier designs. We would most definitely make use of more technical instruments that could, for instance, measure speed or force more accurately. In conclusion, the IMA was a great success, accomplishing all we hoped for. Throughout this project, our group was very efficient and worked very well together and under pressure, creating a Rube-Goldberg device that demonstrated our knowledge of physics, real-world construction, and amicable interaction with others.

7 Resources Patrick Dobbs