<?xml version="1.0" encoding="UTF-8"?>
<tem xmlns="http://www.teachengineering.org/tem/elements/1.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.teachengineering.org/tem/elements/1.0/ http://www.teachengineering.org/schemas/tem.xsd"><identifier>http://www.teachengineering.org/view_lesson.php?url=collection/cub_/lessons/cub_simple/cub_simple_lesson05.xml</identifier><docType>lesson</docType><format>text/xml</format><language/><title>Powerful Pulleys</title><creator>Integrated Teaching and Learning Program, </creator><keywords><keyword>complex</keyword><keyword>fixed</keyword><keyword>force</keyword><keyword>gravity</keyword><keyword>mechanical advantage</keyword><keyword>movable</keyword><keyword>pulley</keyword><keyword>pyramid</keyword><keyword>redirect</keyword><keyword>simple machine</keyword><keyword>work</keyword></keywords><vocabulary><word>Fixed pulley</word><word>Force</word><word>Gravity</word><word>Mechanical advantage</word><word>Movable pulley</word><word>Pulley</word><word>Redirect force</word><word>Simple machine</word><word>Work</word></vocabulary><summary>Students continue to explore the story of building a pyramid, learning about the simple machine called a pulley. They learn how a pulley can be used to change the direction of applied forces and move/lift extremely heavy objects, and the powerful mechanical advantages of using a multiple-pulley system. Students perform a simple demonstration to see the mechanical advantage of using a pulley, and they identify modern day engineering applications of pulleys. In a hands-on activity, they see how a pulley can change the direction of a force, the difference between fixed and movable pulleys, and the mechanical advantage gained with multiple / combined pulleys. They also learn the many ways engineers use pulleys for everyday purposes.</summary><engrConnection>
		
			
				Engineers are experts at exploiting the advantages of simple machines in all sorts of real-world applications that benefit society. They incorporate the mechanical advantage of pulleys into their design of many modern-day structures, machines, products and tools, such as cranes, elevators, flagpoles, zip lines, motors, bicycle rings/chains, clothes lines, water well bucket/rope, rock climbing devices, window blinds and sail/fishing boats. Using multiple pulleys in conjunction with motors and electronics, engineers create complex modern devices that perform much work for very little power.
			
		
	</engrConnection><learningObjectives><learningObjective>Demonstrate how pulleys are used.</learningObjective><learningObjective>Explain how pulleys could have been used by engineers in ancient times to do work. </learningObjective><learningObjective>Identify modern applications in which engineers use pulleys.  </learningObjective></learningObjectives><timeRequired unit="minutes">15</timeRequired><publisher>TeachEngineering.org</publisher><contributors><contributor>Justin Fritts</contributor><contributor>Lawrence E. Carlson</contributor><contributor>Jacquelyn Sullivan</contributor><contributor>Malinda Schaefer Zarske</contributor><contributor>Denise Carlson, with design input from the students in the spring 2005 K-12 Engineering Outreach Corps course.</contributor></contributors><requirements><requires>http://www.teachengineering.org/collection/cub_/lessons/cub_simple/cub_simple_lesson05_presentation.ppt</requires></requirements><references><reference>http://www.dictionary.com</reference></references><eduStandards><eduStandard><id>S11417B7</id><locale>International_Technology_Education_Association-ITEA_STL_Standards</locale><type>Technology</type><description>D. The use of transportation allows people and goods to be moved from place to place.
</description><lowgrade>3</lowgrade><highgrade>5</highgrade></eduStandard></eduStandards><geoCoverage>United States</geoCoverage><rights>Copyright 2012 - Integrated Teaching and Learning Program, College of Engineering, University of Colorado at Boulder</rights><rights>http://www.teachengineering.org/policy_ipp.php</rights><isPartOf>http://www.teachengineering.org/</isPartOf><created type="W3CDTF">2011-03-30</created><gradeLevel lowerbound="3" upperbound="5">4</gradeLevel><audience>Teacher</audience></tem>

