Period+2+Exploring+Friction+Group+2


 * Exploring Friction (Frictionless Group) **

Together with your group, come up with a name for your group in the spirit of our physics unit!
 * Our Group Name: Frictionless**
 * Brianna Figueroa, Erin Foley, Christian Gagliano**

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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 object.


 * Define these two types of friction:**
 * Static Friction –** the friction occurring between two non-moving objects. Vanishes when object is in motion.


 * Sliding Friction –** the friction occurring between multiple objects, when one or more is moving over another

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. As more mass and weight there is, the more newtons it requires to move the wood blocks Static friction appears to be higher than the sliding friction Maximum newtons required to move was 2 newtons Blocks move in jerky motions
 * Observations:**

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 blo ck 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 || 127.4 || 1.24 || 0.4 || 0.3 ||
 * Block 1+2 || 213.9 || 2.09 || 0.6 || 0.5 ||
 * Block 1+2+3 || 354.9 || 3.48 || 1 || 0.8 ||
 * Block 1+2+3+4 || 459.0 || 4.50 || 1.4 || 1 ||
 * Block 1+2+3+4+5 || 592.5 || 5.81 || 2 || 1.4 ||

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 amount of mass increases, all types of friction are increasing. The static friction increases more rapidly than the sliding friction when mass is changed. Also when more mass is added, more weight is shown in the object. Lastly, when the object has more mass and weight, it requires more newtons to move the objects.

5. Create a graph to show the relationship.
 * Identify the independent variable for the x- axis: **Weight**
 * Identify the dependent variable for the y-axis: ** Friction **
 * What type of graph is appropriate for this set of data? ** The effect of weight on an object’s friction **
 * What can be done to distinguish the static friction data set from the sliding friction data set? **Different colored lines and a key**
 * Create the graph using “Create a Graph” or paper and pencil.

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 amount of weight increases, the amount of friction increases. When the amount of friction increases, the newtons required to move it also increases. Lastly, the static friction is generally higher than the sliding friction because of inertia.

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:__ Will increasing the surface area of an object increase the friction acting upon it? __Hypothesis:__ Increasing the object's surface area will increase the friction acting upon it. __Independent Variable:__ Surface area
 * 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: || 1 Block  || 2 Blocks || 3 Blocks || 4 Blocks || 5 Blocks ||
 * Repeated Trials: || 1 || 1 || 1 || 1 || 1 ||

__Dependent Variable:__ Friction (N) __Constants:__ Weight, Mass, surfaces __Procedure:__ __Data Table:__ __ Analysis: __ Our Lab showed that when the surface area of the contacting surfaces of an object is smaller, the friction decreases. When the surface area increases, the friction increases as well. The static friction seems to always be higher than the sliding friction, possibly due to the laws of inertia.
 * 1) Place block on largest surface (measure surface area and record)
 * 2) Pull with scale
 * 3) Record the amount of Newtons required to move it (static and sliding)
 * 4) Repeat for the two other surfaces of the block
 * Objects || Mass (g) || Weight (N) || Static Friction (N) || Sliding Friction (N) ||
 * Block 1 || 127.4 || 1.24 || .2 || .1 ||
 * Block 1+2 || 213.9 || 2.09 || .5 || .3 ||
 * Block 1+2+3 || 354.9 || 3.48 || 1 || .6 ||
 * Block 1+2+3+4 || 459.0 || 4.50 || 1.5 || .8 ||
 * Block 1+2+3+4+5 || 592.5 || 5.81 || 1.8 || 1 ||

__Graph__: