Shipping and Sliding - fpsct.org

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When ocean waves cause the ship to tilt from side to side, ... Shipping and Sliding Task. ... Why? How deep should the shipping crates be stacked?
Shipping and Sliding A Guided Exploration of Factors Affecting Friction

ENGAGE

Many of the products we use are made or grown in other countries and sent here by plane, boat or truck. Some companies that make televisions, for example, put them in wood boxes that are carried here by cargo ships. When ocean waves cause the ship to tilt from side to side, the boxes sometimes slide across the cargo room floor and damage the televisions packed inside. Increasing the friction in the cargo room may solve the problem. The television manufacturer is willing to change the box materials and the shipping company is willing to change the floor materials. Imagine that you have been hired to conduct a friction study that will explore ways to increase the friction force and solve the problem of the sliding boxes.

EXPLORE

First, you and your partners will design and conduct experiments to find out what affects friction. Then, you will analyze your experimental findings to make recommendations to the television manufacturer or the shipping company. Your finding will help you make recommendations about materials to use on the ship or to make the box, the box shape and how to stack the boxes.

MATERIALS Washers and/or weights plastic cups to hold washers Ruler string Wooden blocks-different sizes Masking tape Access to a balance Graph paper A plastic cylinder (a pen, for example) markers

PROBLEM QUESTION CHOICES

1) How does the surface type affect the amount of force needed to move a block of wood?

2) How does mass affect the amount of force needed to move a block of wood?

3) How does surface area affect the amount of force needed to move a block of wood? A Method for Testing Friction:

1. Construct a model shipping box like the one in the diagram below. The paper clip will allow you to pull the box with a measured amount of force:





2. Use a piece of cardboard as a model of a cargo room floor.

3. Tape a plastic cylinder along the edge of your work table. Place the cardboard shipping floor on your work table near the plastic cylinder.

4. Tie a loop at one end of the string and attach the loop to the paper clip. Drape the string over the plastic cylinder and use tape to attach the plastic cup to the other end of the string (see diagram below).













5. By adding small washers to the plastic cup, you can measure the pulling force needed to start the box moving. The more force needed to start the box moving, the greater the friction between the floor and the box materials. You can keep track of the number of washers, or you can find the mass of a single washer and keep track of the total mass needed to start the box moving.



Name: _______________________________________ Date: _______________________ Period: _______ Page: ________

|TESTABLE QUESTION: | | | | | |IV= _______________________ ( ) DV= | |______________________ ( ) |

|PREDICTION: | | | | |

|PROCEDURE: |SCORE | |(Write a short paragraph about how you will test your question.) | | | | What is changing| | |and how is it | | |changing? (IV) | | | | | | How will DV be | | |measured? | | | | | | What will be | | |constant(the | | |same) or | | |controlled? | | | | | | Repeat/multiple | | |trials | | | | | | Clear sequence | | |and complete | | |sentences | DATA:

Title= |IV= |DV= | | |1 2 | | |3 AVERAGE | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |

|FINDINGS: | | |(Write a short paragraph about what your data tells you about your question) |SCORE | | | | | | Echo the original | | |problem question | | | | | | Gives and | | |answer/tell what you| | |found out | | | | | | Supports answer | | |with data examples | | | | | | Make comparisons/ | | |discuss other | | |findings | | | | | |Accept/reject the | | |prediction |

Name: _________________________________________ Date: ________________________ Period: ________ Shipping and Sliding Task | |Below |Near |M- |Meets |M+ |Exceeds | |Procedur|no indication of|limited to description| |All “Near” criteria plus... | |All “Meets” criteria | |e |tested variables|of one variable | |explains observation or | |plus... | | |is evident |incomplete or unclear | |measurement of independent | |effectively reduces | | |not submitted | | |variable | |experimental error | | | | | |explains observation or | |through: multiple | | | | | |measurement of dependent | |trials or large sample| | | | | |variable | |size | | | | | |clear sequence of events | |uses relevant and | | | | | |complete sentences | |important constants | |Data |no organization |data is incomplete or | |All the following with 1 or 2 | |All “meets” criteria | |Table |to data |data organized into | |minor errors | |plus no minor errors | | |not submitted |columns with no labels| |table of trials is neatly drawn| | | | | | | |data is sequenced appropriately| | | | | | | |accurate averages are listed | | | | | | | |informative title, variables, | | | | | | | |trials, averages and units are | | | | | | | |clearly marked | | | |Graph |inappropriate |appropriate graph type| |All the following with 1 or 2 | |All “meets” criteria | | |graph type |with major error (such| |minor errors | |plus no minor errors | | |not submitted |as inaccurate | |appropriate graph type chosen | | | | | |plotting, reversed | |consistent intervals on axes | | | | | |axis, inconsistent | |accurate plotting of averages | | | | | |intervals) | |accurate best fit curve or | | | | | |f | |sorted bars | | | | | | | |informative title, labeled axis| | | | | | | |with units | | | | |answer does not | “answer” is vague | |All “Near” criteria plus... | |All “Meets” criteria | |Findings|reflect data |General support for | |Restates the original question| |plus... | | |not submitted |findings | |Gives a specific reasonable | |Additional relevant | | | | | |“answer” | |findings beyond the | | | | | |Supports with specific relevant| |immediate question OR | | | | | |evidence | |Evidence is compared | | | | | |Accepts or rejects prediction | |to clarify support | | |Disruptive group|Rarely respectful | |Mostly respectful group member | |Always respectful | |Effectiv|member |group member | |Adequate participation | |group member | |e |Limited |Occasional | |Adequate presentation | |Full participation | |Collabor|participation |participation | | | |Effective presentation| |ation |Incomplete |Presentation needs | | | | | | |presentation |revision | | | | |

Use lab findings to create recommendations for the TV manufacturer and the cargo ship company. How can they use friction to protect the TVs? Write a letter to one of the companies with your ideas.

|Problem Question |Findings |What should the |What side of a |How deep should the | | | |shipping crates and/or|shipping box should be|shipping crates be | | | |cargo hold materials |face down? Why? |stacked? Why? | | | |be? Why? | | | | | | | | | | | | | | | |How does the surface | | | | | |type affect the amount| | | | | |of force needed to | | | | | |move a block of wood? | | | | | | | | | | | | | | | | | | | | | | | |How does mass affect | | | | | |the amount of force | | | | | |needed to move a block| | | | | |of wood? | | | | | | | | | | | | | | | | | | | | | | | |How does surface area | | | | | |affect the amount of | | | | | |force needed to move a| | | | | |block of wood? | | | | | | | | | | |

----------------------- board

Plastic cylinder

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