1. 8/25/10 We were testing to see which car would work better and seeing if the balloons would work and if what we need to do to turn it. It traveled about 5in. The velocity was about 1in/s and acelerration was about 0m/s². With this being how our car moves we think our car will probably only go about 5 or 6 inches on race day. The way our car moves relates to the second law because because when you put the ballon down and you let go the ballon is putting force on the car so the car is putting force on the ground. so then the ballon wont go flying around the floor.

8/26/10:what we did is we made our car move well not really move because when we tried to make the car move with the balloon it did not really move. sometimes it will move but not very far so that means the balloon is to weak or the car is to big. it relates to  newtons second law because the air in the balloon is not enough force to push the car (the mass) and make it move and accelerate. This explains how something times zero equals zero. If the acceleration was zero and the mass was about 75g then 0 X 75=0 because if your multiplying something by nothing you won't get anything.

8/26/10: Today we have accomplished making a new rat trap car.  Our result was not what we expected. We learned that we need to keep the balloon up so that it moves quicker. Also we need to figure out which car we are using because we have the new car (on the left in the photo below) and the old car (on the right). We also need to figure out how to make both cars turn.

 <------Justine researching

Today we are still testing our car. We figured out how to make the car move using the balloon but it doesn't move very far. Plus, sometimes it works and sometimes it doesn't. We think the balloon doesn't make the car move too far because the mass of the car is to large for the little air force the balloon gives. We still need to figure out how to make it turn too. Our hypothesis to make the car turn would be to put the front wheels at a diagonal because if the wheels are at a slant we think it will make the car turn.

We are going to make sure that the car turns precisely. We aso are going to try to decorate it if we have time. Also we need to figure out a place to put the mouse, Stewart. It's hard to tell if the car will work all the time because sometimes the balloon makes it go and other times it doesn't. Along with this dilemma, we still have to figure out how to make it turn. It's tough

what we did today we were working on our car to see if it can go on the track on race day. so now we have to see if it will even work so it is pretty tought to do that.it has to do with newton's 3rd law because it has to do with pushing the car froward and the spring is being pushed back

Today we will begin testing our car for an experiment. The technique we are trying is all big wheels on the car. The results were that the big wheels actually make the car go slower and not as far. We think it may be because the friction on the bigger wheels is more than on the smaller wheels.

-Big Wheels:13.81 seconds

-Little Wheels:13.19 seconds

Today we are still testing the car. Because the little wheels made the car go faster we are still using those. The car broke though so we are going to get more materials and fix it over the weekend. We continued our experiment today and figured out the big wheels went 3.5m/s and the little wheels went 4.5m/s.

<----- Here is the chart we made

9/2/10: Today we fixed the car and it worked for the first half of class but then it broke again :(. We also worked on our experiment again. We figured out that we had a couple flaws in our experiment such as we only tested once for each tire and we didn't have a big enough variety of tires. Over the weekend we are going to get bigger wheels and smaller wheels than we already have and test them at least 5 times each.

Today we tested the car again. Testing the car relates to Newtons first law, an object in motion stays in motion unless another force acts upon it, because the car would keep moving if there was no friction on the wheels to stop it. We fixed the car so that we wouldnt have to take off the wheels and adjust the screws to make it turn.So we took a block of wood and stuck it underneath the car and screwed it together then we put 2 hooks on it and put the wheel through it. We did this because whenever we tried to adjust the screws they would fall out. Now we just have to turn the wood that the wheels are on to make it turn, but we have to find the exact angle to twist the wood so that it turns on the track just right. When we find the correct angle we are going to find a way to make it stick in that spot.

<-------Courtney's force diagram of our car going down the track  

Today we tested the car again and it works very well. We figured out the exact angle we need to have the wheels at in order for it to go around the track. It goes around the track 1 ¹/₄ times. My hypothesis on how far the car will go on race day is about 1 lap because the spring is wearing out as the car used to go to laps. As we are obviously going to test the car in the future, the spring will wear out even more and the car will only go around the track once.

We collected data while testing today by writing down the time and distance the car went.

velocity initial (v_i)= 1.833333...m/s

velocity final (v_f)= 3.38m/s

acceleration= .1m/s²

mass= 77.5g

force= 7.74N

^^^Kiersten's Force Diagram of our car

We tested our car again today. It went arond nearly 1¹/₂ times, thats 18 feet.

Here is some of the data we collected.

v_i= 0.6m/s because the distance, 1.5m, divided by the time, 2.5s, is 0.6m/s

v_f= 0.5m/s because the distance, about 5.49m, divided by the time, 10.04s, is about 0.5m/s

a= -0.2m/s² because the final velocity 0.5m/s, minus the initial velocity, 0.6m/s, divided by the distance, about 5.49m, equals about -0.02m/s²

f= -1.55N because the mass, 77.5g, times the acceleration, -0.02m/s², equals -1.55N

As you may have noticed, the results have changed since yesterday. We believe this is because the spring in our spring powered gear box is wearing out so when it spins and turns the gears, it doesn't take as long to unwind. My hypothesis is that if we keep testing the car, it will only go, at most, one lap.

Newtons 2nd Law:F=ma

We did not test the car today due to the fact that the spring is wearing out and we want our car to go at least one lap. Instead, we worked on our force diagrams and our website.

<-----Justine's force diagram of our car going up the bank

We also discussed Scientific Notation. Scientific notation is used to make numbers easier to read. For example: if someone had a decimal, say .0000853, in scientific notation, that number would be 8.53x10^-5. This is because you move the decimal over to the first integer and because the decimal is going 5 spaces to the right, the exponent in the notation is going to be -5.

Another example would be if you had a whole number such as 19,050,000, the scientific notation would be 1.905x10⁷. This is because you move the decimal to the first integer and because the decimal is going 7 spaces to the left, the exponent in the notation is going to be positive 7.

Again, we didn't test the car today due to the whole spring wearing out thing. but we worked on our force diagrams, made a logo for our car, and painted our car too.

<------Here is our painted car

<-------Nicole's force diagram

Today was BACKWARDS DAY!!!!! Backwards day is when we make the car travel in the opposite direction and show how the car isn't going negative numbers. our car traveled -16.5 feet but because you can't travel a negative number it really went 16.5 feet. That explains absolute value. We also tested the car a little to make sure we really had the correct angle of the wheels but we couldn't test it too much because of the whole spring wearing out. If we continue winding up the spring, eventually it will only go half way, which is how far it needs to go, and Kiersten, being an over achiever, would be very upset by this.

We also discussed why multiplying a number by a decimal, such as .5, it gets smaller. The equivelent to .5 is ¹/₂ so if you were to half a number, such as 6, it would equal three.

Also, if you were to multiply a number, such as 3, by a whole number, such as 10, it would equal 30. This is because when you multiply something it's like adding the same number a bunch of times.

If you were to multiply a whole number, such as 5, by a negative number, such as -4, you would get -20. The answer would be negative. Explanation: Its pretty much a subtraction problem. -5-5-5-5=-20