Group+6.1-2-EB

Evan and Aaron Wikipage

Evan Bloom, Aaron Chang, Jimmy Ferrara Lab Report

**Procedure**
Time Graphs: 1. Set up Data Studio on laptop to record distance, velocity, and acceleration. 2. Set up motion sensor on stairs so it is about waist height. 3. One person performed the different types of movements including: 4. Screen shots were taken of each experiment on Data Studio
 * No motion
 * Increasing speed toward
 * Increasing speed away
 * Constant speed toward
 * Constant speed away
 * Decreasing speed toward
 * Decreasing speed away

Ticker Tape Diagrams: 1. Set up spark timer. 2. Insert a piece of ticker tape into the spark timer and turn on the timer without moving the tape. Turn off spark timer and pull out tape. 3. Put a piece of ticker tape into the spark timer and put it through with increasing speed. 4. Put a piece of ticker tape into the spark timer and put it through at a constant speed. 5. Put a piece of ticker tape into the spark timer and put it through with decreasing speed. 6. Take pictures of each strip of ticker tape inserted into the spark timer.

**Analysis and Data Interpretation**

 * 1) ** How can you tell that there is no motion on a… **
 * 2) Motion diagram- There is one big black dot indicating no motion.
 * 3) Ticker tape diagram- The dots on the tape are extremely dark, and rather than there be multiple dots along the tape, they are all concentrated in one spot, resulting in the dark dots.
 * 4) position vs. time graph- There would be a horizontal line at the specific distance that the subject is standing away from the sensor. Since he/she is not getting any closer or farther from the sensor, the distance remains the same.
 * 5) velocity vs. time graph- Since there is no motion, the velocity should be at a constant 0.
 * 6) acceleration vs. time graph- Since nothing is gaining or losing any speed, the acceleration when there is no motion should be constantly at 0.


 * 1) ** How can you tell that your motion is steady on a… **
 * 2) Motion diagram- All of the arrows are pointing in the same direction and are all the same size.
 * 3) Ticker tape diagram- The dots are evenly spaced from each other all along the tape, showing that the speed is staying at a constant pace.
 * 4) position vs. time graph- Since the positioning of the subject is changing at a constant pace, the slope of the graph will also remain the same.
 * 5) velocity vs. time graph- Because the speed of the object does not change, the velocity should also be constant to show steady motion.
 * 6) acceleration vs. time graph- Since the object is not gaining or losing any speed because it is at a constant speed, the acceleration is constant at 0.

 a. Motion diagram- If the motion is fast, then the arrows will become longer and longer to represent increase in speed. If the motion is slow, the arrows will become shorter and shorter to represent decrease in speed.  b. Ticker tape diagram- If the ticker tape is moving quickly through the spark timer, then the dots will be spread out more and if it is moving slowly through the spark timer, then there will be less distance between the dots.  c. Position vs. time graph- If the motion is fast, then the line will have a large slope and if the motion is slow, the line will be more horizontal. d. Velocity vs. time graph- If the motion is fast, then the line will have a steep slope and if the motion is slow, the line will have a smaller slope. e. Acceleration vs. time graph- If motion is fast the line will be below the x-axis and if motion is slow the line will be above the x-axis
 * 3. How can you tell that your motion is fast vs. slow on a... **

a. Motion diagram- If the arrows are pointed in different directions, then the object changed directions. b. Ticker tape diagram- It is impossible to show change in direction with the ticker tape. c. Position vs. time graph- If the graphs for moving toward the motion sensor and moving away from it are opposites, then it indicates a change in direction. d. Velocity vs. time graph- If the graphs for moving toward the motion sensor and moving away from the sensor are reflections of each other then it shows a change in direction. e. Acceleration vs. time graph- You can't tell that you changed direction on an acceleration graph.
 * 4. How can you tell that you changed direction on a...**

a. Motion diagram- the arrows progressively get bigger indicating that motion is increasing. b. Ticker tape diagram- The space in between the dots increases as the speed increases. When the dots start to grow father apart it is apparent that the motion is increasing. c. position vs. time graph- In this case you can tell that motion is increasing simply by observing that the slope is positive. As the line moves up off the x-axis you can tell the motion is increasing because position and time are increasing at the same time. d. velocity vs. time graph- The line being in the first quadrant of the graph indicates increasing motion. f. acceleration vs. time graph- If the constant line is situated above the x-axis it means motion is increasing.
 * 5. How can you tell that your motion is increasing on a… **

<span style="font-family: Arial,Helvetica,sans-serif;">a. Motion diagram- when the arrows start to become smaller, it shows motion is decreasing. <span style="font-family: Arial,Helvetica,sans-serif;">b. Ticker tape diagram- When the dots start to grow closer this means that motion is decreasing. <span style="font-family: Arial,Helvetica,sans-serif;">c. position vs. time graph- Any negative slope indicates that motion is decreasing in this type of graph. The line stretches toward zero, which shows motion is decreasing and getting to a point of no motion. <span style="font-family: Arial,Helvetica,sans-serif;">d. velocity vs. time graph- If the line is in the fourth quadrant motion is decreasing. <span style="font-family: Arial,Helvetica,sans-serif;">f. acceleration vs. time graph- Motion is decreasing in this graph when the constant line is below the x-axis.
 * <span style="font-family: Arial,Helvetica,sans-serif;"> 6. How can you tell that your motion is decreasing on a… **

**Discussion Questions**
1. What are the advantages of representing motion using a... a. Motion diagram- This clearly lets you see if an object is increasing in speed or decreasing in speed. b. Ticker tape diagram- The ticker tape clearly shows the speed of the motion because of the dots on it. c. Position vs. time graph- This lets you know where the object is and in which direction it is moving. d. Velocity vs. time graph- It shows the velocity of an object moving away or toward the sensor. e. Acceleration vs. time graph- This shows the acceleration of an object as it moving back and forth.

<span style="font-family: Arial,Helvetica,sans-serif;">2. What are the disadvantages of representing motion using a… <span style="font-family: Arial,Helvetica,sans-serif;">a. Motion diagram- This type of diagram does not show velocity or acceleration and is very simple. <span style="font-family: Arial,Helvetica,sans-serif;">b. Ticker tape diagram- The only motion this device measures is acceleration, thus you don’t know the direction or position of the object. Also the diagrams are not very exact and it is impossible to get accurate data of acceleration. <span style="font-family: Arial,Helvetica,sans-serif;">c. position vs. time graph- In this graph, the direction in which an object is moving and its acceleration are difficult to interpret quickly. And also the graph does not clearly show motion to the left and right positions. <span style="font-family: Arial,Helvetica,sans-serif;">d. velocity vs. time graph- This graph does not show position nor does it indicate direction clearly, which is a part of velocity. <span style="font-family: Arial,Helvetica,sans-serif;">f. acceleration vs. time graph- It does not show velocity or position, only a change in velocity.

3. Define:
 * 1) No motion- This means that the object in question is not moving closer nor farther from the sensor.
 * 2) Constant speed- Constant speed means the object has both a constant velocity and a constant acceleration of 0 while the distance fluctuates.
 * 3) Increasing speed- Increasing speed means the object gains velocity while acceleration also increases.
 * 4) Decreasing speed- Decreasing speed means the object loses velocity, and acceleration also decreases.

In this lab, there were four types of graphs that we used to measure movement: the ticker tape graph, the distance vs. time graph, the velocity vs. time graph, and the acceleration vs. time graph. We can learn from this lab that velocity and acceleration are very closely related. As velocity increases at a steady pace, acceleration also increases. If velocity decreases, acceleration will also decrease. If velocity is at 0, then acceleration is also at 0. The opposite ways are also true. However, there was some room for error in this lab. <span style="background-color: #ffff00; font-family: 'Comic Sans MS',cursive;">You only addressed the first part of conclusion. You need to explain what the errors are and how to fix them.
 * Conclusion**


 * Evan Bloom, Aaron Chang, Jimmy Ferrara**
 * 9/20/10**

**A Crash Course in Velocity Lab**
 * Hypothesis**
 * 1) The ticker tape attached to the back of the fast car will have longer distances in between the dots, and the tape attached to the slow one will have closer dots. This shows that the faster car will have a greater velocity than the slower car.
 * 2) When both cars are set up to face each other and set off at the same time, the slower car will travel a lesser distance than the faster car.
 * 3) Even though the cars start at the same time, the faster car, which was started at least 1 meter behind the slow car, will catch up to and eventually pass the slow car.

Part I- Ticker Tape Spark Timer Part II- Cars Traveling Towards Each Other Part III- Fast Car Catching Slow Car
 * Procedure**
 * 1) Tape a piece of ticker tape to the back of the fast Constant Motion Vehicle (CMV).
 * 2) Feed the ticker tape through the spark timer until the base of the CMV is close to the timer.
 * 3) Line up a meter stick parallel with the CMV.
 * 4) Turn on both the timer and the vehicle. Once all of the ticker tape has passed through the timer, IMMEDIATELY stop the car and record the time. Make sure at least 20-30 dots are recorded.
 * 5) Repeat steps 1-4 for the slow CMV.
 * 6) Record the distance between each of the dots in centimeters for all of the tapes used.
 * 7) Create a distance-time graph from the information recorded by each piece of the tape.
 * 1) Set up the fast CMV and the slow CMV 600 cm apart, facing towards each other. Make a prediction of how far each car will travel.
 * 2) Have one partner turn on one car, while the other partner simultaneously turns on the other car.
 * 3) Record the distances that each car traveled once the two collide.
 * 4) Repeat steps 1-3 four more times.
 * 1) Set up the slow CMV at least 1 meter in front of the fast CMV, with both cars facing the same direction. Predict how far each car will travel before the fronts of each car are even.
 * 2) Start both cars at the same time and stop both cars once they are at the same location.
 * 3) Record the distances that each car has traveled.
 * 4) Repeat steps 1-3 four more times.


 * Data #1**

FAST CMV SLOW CMV <span style="background-color: #ffff00; font-family: 'Comic Sans MS',cursive; font-size: 110%;">you should have an additional decimal place for these measurements. You can go to hundredths of a cm.
 * Time(s) |||| Distance(cm) || Time(s) || Distance(cm) ||
 * 0.1 || 2.1 ||  || 0.1 || 1.0 ||
 * 0.2 || 4.8 ||  || 0.2 || 1.9 ||
 * 0.3 || 8.5 ||  || 0.3 || 2.7 ||
 * 0.4 || 12.3 ||  || 0.4 || 3.8 ||
 * 0.5 || 16.2 ||  || 0.5 || 5.0 ||
 * 0.6 || 19.9 ||  || 0.6 || 6.1 ||
 * 0.7 || 23.6 ||  || 0.7 || 7.1 ||
 * 0.8 || 27.2 ||  || 0.8 || 8.0 ||
 * 0.9 || 31.1 ||  || 0.9 || 9.3 ||
 * 1.0 || 34.8 ||  || 1.0 || 10.5 ||
 * 1.1 || 38.6 ||  || 1.1 || 11.5 ||
 * 1.2 || 42.4 ||  || 1.2 || 12.5 ||
 * 1.3 || 46.1 ||  || 1.3 || 13.8 ||
 * 1.4 || 49.8 ||  || 1.4 || 14.9 ||
 * 1.5 || 53.4 ||  || 1.5 || 16.0 ||
 * 1.6 || 57.7 ||  || 1.6 || 17.1 ||
 * 1.7 || 60.6 ||  || 1.7 || 18.2 ||
 * 1.8 || 64.0 ||  || 1.8 || 19.2 ||
 * 1.9 || 67.2 ||  || 1.9 || 20.3 ||
 * 2.0 || 70.0 ||  || 2.0 || 21.5 ||
 * ||  ||   || 2.1 || 22.5 ||
 * ||  ||   || 2.2 || 23.5 ||
 * ||  ||   || 2.3 || 24.5 ||
 * ||  ||   || 2.4 || 25.5 ||
 * ||  ||   || 2.5 || 26.5 ||
 * ||  ||   || 2.6 || 27.6 ||
 * ||  ||   || 2.7 || 28.7 ||
 * ||  ||   || 2.8 || 29.7 ||
 * ||  ||   || 2.9 || 30.8 ||
 * ||  ||   || 3.0 || 31.9 ||



<span style="background-color: #ffff00; font-family: 'Comic Sans MS',cursive; font-size: 110%;">These lines should both be on the same graph, in order to compare.


 * Sample Calculations**

Fast CMV Velocity: 35.2 Slow CMV Velocity: 10.6

__CMV Head-on Collision Problem__

__CMV Catch Up Problem__

<span style="background-color: #ffff00; font-family: 'Comic Sans MS',cursive; font-size: 110%;">units, equations used?


 * Data #2**

__CMV Head-on Collision Problem__
 * Trial || Meet Position(cm) ||
 * 1 || 145 ||
 * 2 || 142 ||
 * 3 || 137 ||
 * 4 || 139 ||
 * 5 || 143 ||

__CMV Catch Up Problem__ <span style="background-color: #ffff00; font-family: 'Comic Sans MS',cursive; font-size: 110%;">incomplete: need average of these trials and %error to theoretical
 * Trial || Catch-Up Position(cm) ||
 * 1 || 140 ||
 * 2 || 138 ||
 * 3 || 141 ||
 * 4 || 143 ||
 * 5 || 139 ||
 * Discussion Questions**

1. Why is the slope of the position-time graph equivalent to average velocity? The slope is equivalent to average velocity because in order to find average velocity, you need to calculate distance/time and both of the graphs show distance and time. If you divide the distance by the time on the graph, the answer will be the same as the slope.

2. Why was it okay to set the y-intercept equal to zero? It was okay to set the y-intercept equal to zero because we know that when the object in the experiment is at rest, its position on the graph is at (0,0), which is the y-intercept. Since every graph must start with the object at rest, it is safe to always set the y-intercept equal to zero.

<span style="font-family: Arial,Helvetica,sans-serif;">3. What is the meaning of the R2 value? <span style="font-family: Arial,Helvetica,sans-serif;">The R2 value represents the amount or percentage of deviation the data points were off from a certain fit. In this graph a linear fit was used and the R2 value was close to 0.99 or 99% in both graphs. This means that 99% of the plotted points fit into a linear graph type.

4. Where would the cars meet if their speeds were exactly equal? If their speeds were exactly equal, the cars would meet exactly at the spot that marks the middle of the distance between the two cars at their starting positions.

<span style="font-family: Arial,Helvetica,sans-serif;">5. Sketch position-time graphs to represent the catching up and crashing situations. Show the point where they are at the same place at the same time.

6. Sketch velocity-time graphs to represent the catching up situation. Is there any way to find the points when they are at the same place at the same time?



No, there is no way to determine when the points are at the same time. The velocity-time graph only shows velocity, not position. Therefore, there is no way of knowing where the two cars are located. To do this, a position-time graph would be needed.

<span style="background-color: #ffff00; font-family: 'Comic Sans MS',cursive; font-size: 110%;">missing conclusion