KOH Final Report

Final Report

Key Question:
Basically our objective was to build a self-propelled car with a rat trap or any other sort of creative method. The primary goal of this was to get the car up and over the hill. As long as you did that, you got a grade. But to add more fire to the fuel, the stakes were made a little hire. Not only were you suppose to get your car to go over the hill but you would also be facing other opponents. And essentially the best car was the last one standing or the "King of the Hill". The car that made it to the top of the hill was the winner.

Investigating: 
Rat Trap

We will make a car that is medium in length with a rat trap to propel it.  We used small wooden wheels in both the front and back, with weights in the back to keep the friction between the wheels and ground. To add more friction to the wheels we put balloons and rubber bands on it, so that it didn't go to fast. We then attached a string to the spring and the axel. We then torqued it and spun it until we couldn't anymore. We would then release the rat trap causing the string to pull on the axel and spin the wheels. This enabled the rat trap to go up the hill at a high velocity.

Materials List: Our rat trap will be 15cm x 10cm

• rat trap- $2.50
• cardboard tube- .25 cents
• rubber bands- .10 cents
• string- .20 cents
• plastic rods-  $1.00
• washers- $1.00
• balloons- $1.00
  
  
  

  

  
  

  

  
  

  
  

  
  

Analysis:
first round: We got a first round bye because the judges believed we had one of the top cars in our class. We were very pleased.
Round of 64: In the round of 64, our opponents car was a lot smaller and slower than ours. What made our car so good is that it got to the top quicker than most cars. We easily won this race knocking the car completely backwards, almost causing it to fall off.good
Round of 32: Next was the round of the 32. It was not that much harder. However, this time the opponents car was almost the exact same size as our car. We came out with a victory. This is because our car made it up the hill quicker than the other. We were extremely pleased and started to think we could make it to at least the sweet sixteen. Our car had easily defeated our opponents.
round of 16: This was not the best round for us. We lost this round. It was devastating because our car was better than our opponents. We should not have lost. But when we released our car, the hand got slightly stuck causing the car to be slower than usual. We should not have lost. We lost because our hand got in the way. bummer!!!!

To be honest, I thought our car was at least an elite eight car. I did too! If it wasn't for that small mistake, I believe our car could have made it to the final... maybe even won it all. However, we didn't and thats just life. We were extremely pleased with our car. It turned out to work a lot better than we had expected it to. We did not think that it would get up the hill as fast as it did. It felt good to create something that worked extremely well and almost carried us to victory if not for a minor error. Besides that small error, we were extremely pleased with this project and recommend it to others. good!

Developing Model:

We are making a car with a light frame and a rat trap to give it a lot of power. There are four forces acting on our car: normal force, force of gravity, force of push, and friction force. We added weights on the back so that gravity keeps friction between the wheels and the ground. The balloons and rubber bands will also create friction with the ramp. Our car had a large acceleration at the beginning hoping that it will be fast enough to reach the top of the hill. Our car will  accelerate and have the highest velocity at the base of the ramp and decrease as it goes towards the top. Incorporating Newtons laws, our car demonstrates Newton's 1st law which is "A body in motion will stay in motion unless an outside force acts upon it and a body at rest will stay at rest unless an outside force acts upon it." The rat trap car will stay in motion until the trigger bar runs out of string to pull. Plus, the car will slow from friction. Our rat trap also demonstrates Newton's 3rd law of motion which is "For every action there is an equal but opposite reaction." In this case when the trap is set off (action) the car propels (reaction). The opposite reaction is that the car propels forward starting from being still to its opposite movement which is moving. This speed combined with the medium mass of the car should enable our car to easily make it up the hill. Although our opponent may be stronger and have more mass we can still successfully beat theme by beating them up the hill. Lastly, there will be a change in momentum in our car when it hits our opponents car. The car with the greater mass, velocity, and momentum will win the battle. This speed combined with the medium mass of the car will create enough momentum to destroy any car on the track.

Evidence:
Yes, I do believe we were extremely successful. To be honest, I had a lot of doubt coming into this project because I didn't believe we could build a good car.why not? However, we were able to complete a really successful car. We were successful because we built a car that successfully could go up a hill. We were able to get the right materials and successfully build a car that could not only go up a ramp but also defeat other opponents. I believe were most successful because of our velocity. Our car did not weigh to much and we had really strong wheels with the perfect amount of friction. This enabled our car to be the first one up the hill almost every time. Its large acceleration at the beginning was key and its medium weight helped stop other strong cars. Our car just had more momentum and a higher velocity. However, there were some cars that stood out more than others. The cars that were the most successful used some type of really strong string or bungy chord to push it up the hill. What also helped cars reach the later stages was some sort of ramp attached to the front of the car. I thought that was extremely interesting. If i was to do this project again, i probably would not change my car up to much. The only thing I might do is add a little ramp to the front of my car and use some type of flexible chord or bunny chord. Other than that, I believed my car could have won it all. If it wasn't for that minor mistake of getting the hand stuck, I believe we could have won it all.

Ticker Tape Lab

Ticker Tape Lab

Key Question:  What is the relationship between position and time for a cart rolling down a ramp?

What is the relationship between velocity and time for a cart rolling down a ramp?

Summary: In order to get my position and time data, I first started by using the ticker timer and plugging it into the wall. I then fed the tape (carbon) threw the ticker timer until the car was close to the timer. I then proceded to start the car and ticker timer. This ticker timer produced 6 dots per 0.1 seconds. I then followed this by counting on the tape six dots and making a mark every 6 dots. These six dots represented 0.1 seconds. I did this till I had 1 full second and measured the distance from 0 cm for all the marks(every 6 dots). We then input our data and graphed it.good

Position Graph:

Data Analysis: 

VM: As time increases at a constant rate, the position increases at increasing rate.

MM:  x=(13.357cm/s^2 )t^2

Velocity Graph:

VM: As the time increases increases, the velocity increases proportionally.
MM: y=mx +b
Vf= At + vi
Slope = cm/s/s  <--- acceleration
Description: After creating our position graph, we created our velocity graph in person. We did this by cutting each ticker tape with each six dots. We then kept on doing this until all of it was cut. By cutting it at each 6 dots, we were able to keep the same time interval. We then noticed that as the time increased at a constant rate, the position increases at increasing rate. To create a velocity time graph from a position time graph you have to divide the displacement of each interval by the time of each interval. The result will be the average velocity of each interval. This enables us to see the difference in speed. This graph tells me that the velocity is increasing constantly over a period of time.
good!!!

Investigating:

Two new Equations:

V final = at + V initial

We found this from y = mx + b, which is used to state the equation of the velocity graph.

displacement or x = 1/2(at)^2 

We found this equation by looking at the similarities between the velocity and position graphs, and how their slopes were connected or related.

Area under velocity graph: The area under the velocity graph represents the displacement of car. In essence, the area under the line represents the final position minus the initial position.
good Explaining:
Did each have the same numbers for the constants and slopes?  Why or why not?
No not everyone had the same numbers for the constants and slope. First of all this is because the tape length varied among people. Some had longer tapes than others. Secondly, not everyone had the same slope. This is because they angled their ramp differently. yes Some had ramps at higher positions and some had ramps at lower positions. Thus it would be hard for everyone to get the same results. Although not everyone had the same results, some were similar and close to one another.

  Discuss any errors in your experiment and how you could correct them.
This was a relatively easy experiment but I might have made some errors in my experiment. One of the errors was that my measurements in cm of the ticker tape might have been a little off. Therefore causing my data not to be 100% correct. Their really is no way to fix this besides being the most careful and specific measurer. This will enable your data to be better and give you better results. Another error was that the ticker tape might have had some extra dots on the tape from a previous try. We could of fixed this by using a different ticker tape. This would have given us more accurate and precise data.

Discuss another idea for something you would like to test regarding acceleration and how you could test it.

Another idea for something I would want to test would involve mass. I want to test whether a heavier car enables the car to go faster or slower on the ramp. I could test this by basically repeating this experiment. However, I would use two differently weighted cars, a heavy one and a lighter one. I would then gather the data and compare which one went the fastest on the same ramp. The ramp would have to have the same slope for both cars.
great ideas!!!

Rat Trap Plan and Justification

Jake Holdmann -- Abdula
Tommy Franceschini
Rat Trap

We will make a car that is medium in length with a rat trap to propel it.  We will also use smaller wheels in both the front and back, with weights in the back to keep the friction between the wheels and ground.

be careful of total length!!

Materials List: Our rat trap will be 15cm x 10cm

• rat trap- $2.50
• cardboard tube- .25 cents
• rubber bands- .10 cents
• string- .20 cents
• plastic rods-  $1.00
• washers- $1.00
• balloons- $1.00

Justification
We are making a car with a light frame and a rat trap to give it a lot of power.  We will add weights on the back so that gravity keeps friction between the wheels and the ground  good idea The balloons and rubber bands will also create friction with the ramp.  Our car will have a large acceleration at the beginning hoping that it will be fast enough to reach the top of the hill.  This speed combined with the medium mass of the car will create enough momentum to destroy any car on the track.

what about all the rest of the physics explanation??

Marshmallow Lab

Marshmallow Lab

How will the length of the tube affect the distance the marshmallow travels?

IV: The length of the tube

DV: The distance marshmallow travels

CV: How hard we blow and the height we blow at.

For this experiment we will test if the length of the tube will affect the distance the marshmallow travels. First of all, we had to cut three rectangles out from manila folders. We than created three tubes of 3 different lengths. We will keep the height of the tube the same 160 cm and we will blow the same amount for each one. We will then shoot the marshmallow three times at each tube length: 46.5 cm, 34.2 cm, 22.5 cm. We will than measure the distance the marshmallow travels each time. It is also important to note that each time we blew into the tube the marshmallow was on the same end that we were blowing into. We then recorded the distance. good

Long (46.5cm)	Medium (34.2cm)	Short (22.5cm)
7m	6.21m	3.9m
8.45m	7.6m	4.1m
9.26m	8m	3.7m
Avg= 8.24m	Avg= 7.27m	Avg= 3.9m

**Blowing the hardest at same height of160cm**

Verbal Statements: After doing this experiment, we found that as the length of the tube increases, the distance of the marshmallow from the point in which you started increases. 

How will changing the amount of blow affect the distance the marshmallow travel?

IV: Force of the air

DV: The distance the marshmallow travels

CV: The height of the tube and the tube length.

Basically repeated the exact same procedure except that for this experiment we will test if the strength of the blow will affect the distance the marshmallow travels. We will keep the tube length the same and height of the tube the same, we will use the 22.5cm tube and blow at 160cm. We will then blow soft, medium, and hard. We will do this three times each and measure how far the marshmallow traveled each time and then average the data.

Soft	Medium	Hardest
3m	4.3m	6.2m
2.65m	4.3m	7m
3.55m	4m	7.1m
Avg= 3.1m	Avg= 4.2m	Avg= 6.77m

**22.5 cm tube at 160cm**

Verbal Statement: As the force of the blow increases, the distance of the marshmallow from the starting point increases. In this experiment we kept everything the same except for how hard we blew (soft, medium, hardest).

good

How will changing the height the marshmallow is shot at affect the distance traveled by the marshmallow?

IV: The height where the marshmallow is blown at

DV: The distance the marshmallow travels

CV: How hard the blow is and the length of the tube

Basically repeated the exact same procedure except that for this experiment t we will test if blowing the marshmallow at different heights will affect the distance the marshmallow travels. We will keep the tube length at 22.5cm. We will also blow with the same force each time. We will then test each height three times at .5m, 1m, and 1.5m. We will measure the distance traveled by the marshmallow each time and average the data at the end.

.5m (height)	1m (height)	1.5m (height)
2.6m	3.5m	5.8m
2.5m	3.6m	5.7m
2.7m	3.65m	5.95m
Avg= 2.6m	Avg=3.58m	Avg=5.82m

**Different heights, same tube length (22.5cm), blowing hardest**

Verbal Statement:  As the height of the shooter increases, the distance of the marshmallow from the starting point increases. In this experiment, the height is the only thing being altered.

all excellent!

Conclusion

In the marshmallow experiment we came up with the equation F x t=  (Delta) mv
For the equation above these are the meanings of the terms/symbols: f (force), t (time), m (mass) and  v (change in velocity). Technically speaking F x t is also known as p  J (impulse). Another way to write this equation is j=delta p. J is the amount of impulse and delta p p is momentum ... an impulse causes a change in momentum is basically the product of the force and time.


Using this equation for Experiment 1, as the time the marshmallow experiences the force of the tube increases, the change in velocity increases proportionally. The longer the tube, the longer it takes for the marshmallow to travel through the tube. This will result in the marshmallow traveling greater distance because of the increased velocity. For instance, in our experiment, on average the long tube (46.5 Cm) shot the marshmallow 8.24 M, the medium tube (34.2 M) shot 7.27 M, and the short tube (22.5 M) shot 3.9 meters. This clearly demonstrates that the longer the tube the greater the distance it travels and the shorter the distance the less it travels. This is ultimately due to the amount of time in the tube. because the force has longer time to act on the mallow, speeding it up more

In experiment 2, we found that as the force of the blow increases, the distance of the marshmallow from the starting point increases as well. This could be proved by the following equation, J= delta x p. This basically means that marshmallow will travel the farthest during the hardest blow. This is because if the force acting upon the marshmallow is increasing, the velocity is proportional with it. Therefore, it would gain velocity as well. ??In essence the greater the impulse, the greater the velocity. Therefore, it travels the farthest during the hardest blow. This could be proved from our data and results. The soft blow averaged about 3.1 M, the medium blow averaged 4.2 M, and the hardest blow averaged 6.77 M.

In Experiment 3, we found that as the height of the shooter increases, the distance of the marshmallow from the starting point increases. In this experiment, the height is the only thing being altered. Therefore the speed remains the same and the marshmallow experiences the same amount of force. It also experiences the same amount of time and impulse. So therefore the marshmallow is leaving the tube at the same speed. The reason why the higher height (1.5 M) traveled a greater distance was due to the fact that the marshmallow had more time to hit the ground than the shorter height (.5M). Therefore it is able to travel a greater distance. This can be proved from a data from which we tested 3 different heights. Are averages for the three heights were:  the short shot at .5m hit the ground at 2.6M, the 1M height hit the ground at 3.58M and the 1.5M height hit the ground at 5.82 M.  This set of trials did not test how the independent variables affect the momentum like the other two. However, it proved how the object will travel a greater distance when acted upon from a taller height.good

Error Analysis proofread!  lots of spelling errors in this paragraph
We tried are best not to have any errors in our experiment. However, there was a few things in which we had errors and things that we could have done better. One thing that went wrong in our experiment was that we didn't use the same marshmallow throughout the experiment. Some were larger than others and some were small. Another possible problem was that we used flower some times and maybe that had an affect in which some were shot father. Lastly, our measurements might not have been a hundred percent correct. Next time we should be more precise with our calculations. We could expand upon this experiment by testing other things like if the mass of the marshmallow affects the distance. I really enjoyed this experiment and would recommend it to everyone. me too!  nice job!

Forces Practice: Draw Free Body Diagrams, follow my steps and SHOW ALL YOUR WORK

Friday Practice- BFPM

Friction Lab

Friction Lab

Experiment 1

Pre-Lab Notes:
Experiment 1:  How is the friction force affected when the surfaces are pressed together more?
IV: Normal Force
DV: Friction Force
CV: Velocity, Surface Area
Secondary Experiment: Change the surface.
Prediction: If the surface forces are pressed harder together, the friction force will increase.
Apparatus (list): A surface, a block with felt on one side and rubber on the other side, lab quest mini, computer, dual force sensor, masses

Procedure: First we are going to find the weight MASSof the block and convert it into Newtons. Next, we are going to chose one side of the block, the felt or the rubber, and we are going to drag (pull) the sensor with the block attached to it. After this we will take the data from the testing with the sensor. We are then going to add various masses to the block and redo the same experiment but with more mass on the block. We will do this two times for each side of the object (felt and rubber).not super clear how your measurements became Ff and Fn
Data Collection and Analysis
Primary Experiment (felt side):

VM: As the normal force increases, the force of friction increases proportionally.

MM: Ff= (.1813 N/N) x Fn - .011N

Slope: For every 1N added to Fn, the force of friction increases by .1813 Newtons.

Y intercept: When Fn (newtons) is at zero, the force of friction is -.011Newtons.

Secondary Experiment (rough side):

VM: As the normal force increases, the force of friction increases proportionally.

MM: Ff (1.2538 N/N) x Fn - .4991N

Slope: For every 1N added to Fn, the force of friction increases by 1.2538 Newtons.

Y intercept:  When Fn (newtons) is at zero, the force of friction is -.4991 Newtons.

Experiment 2: How does the Velocity affect the force of Friction?
IV: Velocity
DV: Ff
CV: Fn (Mass), Surface materials

Apparatus: A surface, a block with felt on one side and rubber on the other side, lab quest mini, computer, dual force sensor, masses
Procedure: In order to test how the velocity affects the force of friction, i will use the friction block (felt side) and pull at different speeds. Then im going to measure the force of friction using the force probe at each speed. I will be sure to keep the same mass (fn) and surface.

Force of Friction vs. Velocity

Force of Friction is not affected by the velocity.

Experiment 3: How does the surface area affect the force of Friction?
IV: Surface Area
DV: Ff
CV: Speed, Surface materials

Procedure: First we will get a big block of wood where we can change the surface area. After we know how much surface area each side of the block has, we will test the force of friction on each side of the wood by pulling it with the dual force sensor. During this experiment we will drag the piece of wood at a constant speed and we will keep the same surface material.

Data Collection and Analysis

Force of friction is constant

Conclusion         

In the Friction Lab experiments, we had to test how various actions would change or affect the force of friction. To do this we did 3 different experiments. In the first experiment we tested whether the friction force was affected when the surfaces are pressed together. In the second experiment we tested whether the velocity affected the force of friction. And lastly for the third experiment we tested whether the surface area affected the force of friction. Ultimately, we found out that only changing the amount of pressure of an object will affect the the force of friction. Furthermore, changing the velocity and the surface area does not affect the force of friction. So, in the big picture, this lab helped our study of friction because now we recognize applying more pressure is the only way that the force of friction changes.and changing the surface itself

For Experiment one, after doing this lab and graphing the data, I noticed that everyone had very similar graphs with proportionally increasing force of friction as the normal force increases. In comparison to other groups, our normal force and force of friction were slightly different. But they were generally all relatively the same. The reason both graphs have different slopes is because the amount of friction that each side of the block gives up is different, hence one side is felt and one is rubber. The felt side of the block has a smaller slope because it produces the least amount of friction. However, the rubber side has a larger slope because the rubber material causes more friction because it is preventing movement. The slope basically represents the material (felt or rubber) and therefore corresponds to the surface that is on the block as it creates creates friction. The more friction that is created, the larger the slope, the less friction that is created, the smaller the slope will be. To calculate the force of friction you have to use this equation : F(f)=µ(fn). This is called the coefficient of friction.

For Experiment two, we were testing whether the velocity affected the force of friction. After, testing this and graphing this experiment as a class we noticed that the force of friction was not affected by the the velocity. For experiment three, we tested whether the surface area affected the force of friction as class as well. After testing the experiment and graphing it, we found that the force of friction was constant. Therefore, the force of friction was not affected by the surface area. Both of these experiments came out the exact way i predicted. I thought that neither of them would affect the force of friction.

It is possible for two people wearing identical shoes to have different forces of friction because of two big factors, the mass and the surface. These two factors are what cause the force of friction to vary. Therefore, if two people have different masses, then the one with the heavy mass has more force of friction than the person that has a smaller mass. This is due to the normal force. Futhermore, if they are on different surfaces, there forces of friction will be different because some surfaces may be rougher and some may be smoother. 

It is possible for two people wearing different types of shoes to have the same amount of friction. However, the two people must have different masses. They can not have the same mass. The shoe with more friction must be worn by a lighter person and the won with less friction worn by a heavier person.
So in summary, the mass and the type of surface determine how much force of friction an object will feel/have. However, friction does not depend on the amount of surface area in between the moving object or the speed of the object.

One main source of error that I saw was the use of different tables. Some of these tables may have been sticky, bumpy, and or not the same. This error can be fixed by using one single table that is cleaned and that every group uses. This way everyone can get the same or about the same data without these factors messing up our data. Another source of error would be the method of pulling the vinyl side of the block. This is because the vinyl side had more friction causing it to be more jerky and harder to pull. We could have fixed this by just pulling at a constant speed and not trying to pull harder when the friction would slow it down and cause it to jerk around.
I am very interested in friction due to this lab. I want to learn more in depth about it. I want to know how to determine the strength of the friction and the main types of friction.

After completing this lab, i was very happy. I thought this was a very successful lab. I thought everything went well except for our sources of error. Furthermore, I believe I am becoming better at writing labs in physics class. Every lab i do becomes easier and easier to write. Practice makes perfect and I really enjoy these labs. And I hope to write better on each one.

excellent work Tommy!