Period+2+Exploring+Friction+Group+6

Together with your group, come up with a name for your group in the spirit of our physics unit!
 * Exploring Friction **  ** (Kaitlyn, Keely, and Holly) **
 * Our Group Name:** //The Program//

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 * Work through this lab as a group. Try to encourage everyone to be involved, have a voice, and use their skills!**

What is the definition of **friction**? //The resistance that one surface or object encounters when moving over another//

Define these two types of friction: //Friction between two objects in contact that are not moving. Generally greater than kinetic friction and must be overcome before an object can be set in motion// //The friction between two objects that are in sliding contact//
 * Static Friction** –
 * Sliding Friction** –

Use the blocks, masses, and spring scale to make observations on the amount of force needed to get a mass moving and the amount of force needed to keep the mass moving. Write down your observations.
 * Observations:**
 * // The force it takes for an object to move is greater than the force it takes to keep the object moving //
 * //The static and sliding friction increased as more blocks were added//

Spring scales measure force. Weight is the force on an object due to gravity but a spring scale can also measure the force needed to pull an object. If the spring scale reads 100 g it means that the force is about 1 N. If the spring scale reads 200 g it means that the force is about 2 N.
 * About the spring scale –**

A triple beam balance measures mass in grams. Since w=mg where w is weight in N, m is mass in kg, and g is 9.8 (acceleration due to gravity) then we can convert the mass on our balance to weight using the formula below. Weight (N) = Mass (kg) X 9.8 or Weight (N) = Mass (g) X 0.0098
 * About the triple beam balance –**

1. Experiment by pulling the block with the hook using the spring scale. Lay the block down on the table so that the largest surface is in contact with the table. Try applying such a small force that the block doesn’t move. What did the scale read when the block just begins to move? __g =__ N //This number represents the force of static friction between the block and the table.//
 * Conduct an Experiment**

2. Continue pulling the block across the table at a steady speed. What did the scale read as you pulled the block at a steady speed? __g =__ N //This number represents the force of sliding friction between the block and the table.//

3. Create a data table to record the forces of static and sliding friction as you increase the mass of the blocks/objects you pull across the table. Be sure to convert the mass to weight using the formula above. Create another row for each set of blocks you pull.
 * Objects || Mass (g) || Weight (N) || Static Friction (N) || Sliding Friction (N) ||
 * Block 1 || 130.3 || 1.3 || .4 || .3 ||
 * Block 1+2 || 291.8 || 2.8 || 1 || .8 ||
 * Block 1+2+3 || 397.5 || 3.9 || 1.4 || 1.2 ||
 * Block 1+2+3+4 || 491.6 || 4.8 || 1.8 || 1.4 ||
 * Block 1+2+3+4+5 || 647.3 || 6.3 || 2.4 || 1.8 ||
 * Weight (N) = Mass (kg) X 9.8**

__**Masses of Each Block**__ 1)130.3 grams 2)161.5 grams 3)105.7 grams 4) 94.1 grams 5) 155.7 grams

4. Stop and analyze the data in your table. Describe the relationship between the weight of the objects you pulled and each type of friction. What is the pattern seen in the table? **//As the weight increases, the amount of friction increases.//**

5. Create a graph to show the relationship.
 * Identify the independent variable for the x- axis: **//Weight (N)//**
 * Identify the dependent variable for the y-axis: **//Sliding & Static Friction (N)//**
 * What type of graph is appropriate for this set of data? **//Scatter Plot//**
 * What can be done to distinguish the static friction data set from the sliding friction data set? **//Set static friction and sliding friction as different colors//**
 * Create the graph using “Create a Graph” or paper and pencil.

Graphs


6. Stop and analyze the graph of your data. Describe the correlation between the weight of the objects you pulled and each type of friction. How is the correlation shown in the graph?
 * // As the weight increased both the static and sliding friction increased with it. Trough out the whole experiment the static friction was continuously higher than the sliding friction. This is because it takes more force to start pulling an object than to keep it pulling. //**

Choose a question from below or develop your own unique question with your lab group. Design and conduct an experiment to help find the answer to the question. Complete an experimental design diagram and have it approved before beginning. __Experimental Design Diagram__ __Question:__ What will happen when we take blocks one two and three and compare the sliding/ static friction to those of different surfaces? __Hypothesis:__ Depending on the surface, the forces will either increase or decrease from the amount of force it took for the blocks to move across the colorful tables. __Independent Variable:__ The surfaces that the blocks are pulled across. Surfaces || (Control)  Yellow Table || Black Table || Library Carpet || Tile Floor ||
 * Your Turn**
 * 1) How would the amount of static and sliding friction change if the bottom block was placed so the smaller surface was in contact with the table?
 * 2) How would the amount of static and sliding friction change if the blocks were placed on a different surface?
 * Levels of the IV:
 * Repeated Trials: || 1 || 1 || 1 || 1 ||

__Dependent Variable:__ Sliding and static friction __Constants:__ the blocks, spring scales __Procedure:__ Measure the static and sliding friction of blocks 1 + 2 + 3 + 4 + 5 on different surfaces and record them in the data table. __Data Table:__ table || 647.3 || 6.3 || 2.4 || 1.8 || table || 647.3 || 6.3 || 1,8 || 1.6 || carpet || 647.3 || 6.3 || 1.2 || 1 || floor || 647.3 || 6.3 || 1.6 || 1.4 ||
 * || Mass (N) || Weight (N) || Static Friction (N) || Sliding Friction (N) ||
 * yellow
 * black
 * library
 * tile

__Graph:__



__Analysis:__ The data showed that the carpet had the least amount of both sliding and static friction. However, the hypothesis was that the library carpet would have the most sliding and static friction. The yellow table ended up having the most friction and the library carpet had the least, which was the opposite of the prediction.