Printer Friendly

One zany device: teens compete in an off-the-wall contest with their one-of-a-kind contraption.

[ILLUSTRATION OMITTED]

Sixteen students from Thorp High School in Wisconsin spent two months figuring out how to change a fight bulb. That's because these teens were preparing to compete in Purdue University's Rube Goldberg Machine Contest. The goal: Build the wackiest contraption that performs a simple task in the most complicated manner that a team can possibly concoct.

[ILLUSTRATION OMITTED]

The contest takes its cue from Rube Goldberg, a 20th-century engineer turned cartoonist. His drawings of chain-reaction contraptions--each a crazy collection of household items and everyday objects--put a humorous spin on the idea of time-saving inventions. For the 2009 contest, each machine had to swap an incandescent light bulb for a more energy-efficient one.

Thorp's team modeled its device after a coal mine. Constructing it involved a lot of trial and error. "We put one thing on and then said, 'Well, with their one-of-a-kind contraption it's not working here,' so then we'd move it," says 17-year-old Derek Haas. The key: Connect simple machines, such as levers and screws, to build a compound machine. Simple machines use physical laws to make work easier--for instance, allowing you to move a much heavier weight than you could alone. This idea helped the team to construct a prize-winning contraption that changed a light bulb in 60 steps.

ON A ROLL

The team got its machine rolling by sending a coal cart along an inclined plane. This type of simple machine consists of an upward or downward slanting surface that allows a load to be moved with less force. To get the idea, imagine how tough riding a bicycle straight up a mountain would be. But following zigzagging trails--a series of inclined planes--makes the task easier. Phil Schewe, a physicist at the American Institute of Physics, explains, "You're actually making the route longer, but by switching back, you make the effort in any one moment a lot easier." On the way down, a similar zigzag trail of inclined planes helps keep your bicycle from gaining too much momentum (mass times velocity) and losing control. Team Thorp set up its inclined plane to send its coal cart downhill in a controlled manner.

POWER LIFTER

Next, Haas and his team added to their contraption a lever--an arm that rests on a pivot point, or fulcrum. The coal cart hit the lever, which acted like a crowbar, knocking a miniature boulder loose. The placement of the lever had to be just right: "If you're twice as far away from the fulcrum, you get double the leverage, which is to say you can lift twice as much weight," says Schewe.

Without that lever, the coal cart wouldn't have had enough strength to loosen the boulder--which in turn passed the chain reaction on to such items as toppling steps, falling barrels, sifting sand, and teeter-totters.

THAT'S TWISTED

On step 38, a screw turned. This simple machine is really an inclined plane wrapped around a shaft, the way a sloping trail winds around a mountain. This design is hat makes turning a screw easier than pushing it straight into a wall. Schewe says, "Just as it's easier to walk up a gentle trail than a steep trail, it's easier to put a screw into a wall if the thread of the screw meets the wall at an angle."

Team Thorp's screw rotated a crane to remove the incandescent bulb. On step 60, another screw turned a crane to spin an energy-efficient bulb into the socket. The bulb lit up--and so did the judges' faces. Team Thorp won first place for using simple machines to build a device that's anything but simple.

TEACHERS: Download a PowerPoint on Rube Goldberg machines at: www.scholastic.com /scienceworld

web extra

For more on Rube Goldberg and the contest that bears his name, visit: www.scholastic.com/scienceworld

PHYSICAL: Machines One Zany Device

PRE-READING PROMPTS:

* Who was Rube Goldberg?

* What is the difference between a simple machine and a compound machine?

* Do you think it would be difficult to make a machine that performs a simple task using many complex steps?

DID YOU KNOW?

* Rube Goldberg lived from 1883 to 1970. His first job after graduating from college was as an engineer at the San Francisco, California, Water and Sewers Department. He worked there only six months before becoming an office helper at a newspaper, where he regularly submitted cartoons until they finally published his work.

* Archimedes, a Greek mathematician, invented the first screw. He wanted to remove water that leaked into the hold of a warship. By turning the screw within a cylinder, sailors could easily pump the water overboard.

* The very first Rube Goldberg Machine Contest was held in 1949 as part of the Engineer's Ball at Purdue University. The contest has been held on and off ever since.

CRITICAL THINKING:

* The challenge in the 2009 Rube Goldberg contest was to replace an incandescent light bulb with a more energy-efficient design. Purdue University has announced that the 2010 task will be to dispense an appropriate amount of hand sanitizer into someone's hand. What ideas do you have for future contest tasks?

CROSS-CURRICULAR CONNECTIONS:

ART: You can use the six types of simple machines--levers, pulleys, screws, inclined planes, wheels and axles, and wedges--to make your own Rube Goldberg machine. Draw or build a Rube Goldberg machine that can squirt toothpaste onto a toothbrush. Use at least 10 steps!

RESOURCES

You can access these Web links at www.scholastic.com/scienceworld.

* Download Science World's PowerPoint about Rube Goldberg Machines at: www.scholastic.com/scienceworld.

* Play this interactive game that teaches you about simple machines in and around your house at www.edheads.org/activities/simple-Machines.

* Read the transcript of an interview with Rube Goldberg that was conducted before an exhibit of his cartoons opened at the Smithsonian Institution in 1970: www.aaa.si.edu/collections /oralhistories/transcripts/goldbe70.htm.

* Play this interactive game to create a hamburger-delivering Rube Goldberg device: http://pbskids.org/zoom/games/goldburgertogo/index.html.

DIRECTIONS: Define the following terms in your own words. Use complete sentences.

1. compound machine

2. inclined plane

3. lever

ANSWERS

1. A compound machine is a machine that is made from two or more simple machines connected together.

2. An inclined plane is a simple machine that consists of an upward or downward slanting surface that allows a load to be moved with less force.

3. A lever is an arm that rests on a pivot point, or fulcrum.
COPYRIGHT 2010 Scholastic, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2010 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:PHYSICAL: MACHINES
Author:Adams, Jacqueline
Publication:Science World
Geographic Code:1USA
Date:Feb 1, 2010
Words:1072
Previous Article:I want that job! Steve Vailey is a marine biologist. He works to preserve ocean life by educating aquarium visitors through live-animal exhibits.
Next Article:Cocooned car.
Topics:

Terms of use | Copyright © 2017 Farlex, Inc. | Feedback | For webmasters