9-14-10

 Today was backwards day. Instaed of propelling our car one way down the track, we went the other way. You may think that this would mean that our car would go a negative distance, but as the following graph will show, it is still travelling and therefore does move a positive distance: 

By using absolute value, you still get a positive difference or distance. This also works for one ofe newton's laws, F=ma. Because you cannot have negative force, absolute value is used for force. While most of the work today was on the computerand on the blueprints, we did run some tests on the round track. However, we did not get very much data because another angry group wanted the track right then. We then took the car to our own table to test the turning system. We tested three different ways to launch the caon race day: straight, turned right, or turned left. This test we could not complete either, because it was time to clean up. However, we do know that the straight one and the right-faced one went about 1 meter.

-Tanner

9-13-10

Today, I (Tristan) made a force diagram of Newton's First Law. We also did 3 tests on a straight track in the hallway. The mass of our car is 318 grams and the average of our accelerations is: - 2.34, so our average force is 745.18N.

This is our information:

All of the averages are: Ti = 1.89 seconds, Tf = 8.66 seconds, Vi = 8.12 m/s, Vf = 1.31 m/s, A = - 2.34, F = 744.12, and M = 318.

Newton's First Law states that an object in motion stays in motion until an outside force acts upon it and a still object stays still until an outside force acts upon it. For us, the outside force acting upon our car is the spring and what is stopping our car is the friction on the ground. This is the force diagram representing that:

Our lessons in math while doing this project are absolute value, number sense, and scientific notation. For backwards day tomorrow we will use absolute value to show that even though we went backwards, we still went a certain distance from the starting point, and by using absolute value we simply change the negative into positive to represent this. When multiplying or dividing a number by a decimal, the effect is reversed from the usual effect of growing with multiplication and shrinking with division to the shrinking with multiplication and growing with division (4 times .5 = 2, 4/.5=8, -4 times .5 is -2, -4/.5 is -8) This is because when you divide by a decimal, it would be cut into pieces smaller than whole numbers, making the total "area" of the number larger. With multiplication, the "area" of the number is decreased because the numbers of area “squares” are increased, but they are much smaller and therefore take up less area. With long numbers, sometimes it is faster to write in scientific notation than standard notation. The difference between them is: one has a single digit followed by a sequence of decimals multiplied by 10 to the (however many digits slid) power (10*4 times 6.784502759 instead of 67845.02759). This is useful for numbers like 10,000,000,000,000,000,000,000,000,000,000,000,000 or .000000000000000000000000000000000000000000000000000001, bringing them down to around 10 digits.

~Tristan and Tanner

9-7-10

Today we are devoloping our turning system, the bankings on the track are simply not enough to get the car all the way around the track. our turning system is pretty simple and pertains to Newton's first law. When the car is set on the track it is aty rest and it will remain at rest unless we propell it just like in Newton's first law. When we launch it the rope sort of guides it and forces it to not hit the outside railing of the track. Our only problem is that it may hit the interior railing of the track, the string will have to be the perfect length to avoid this, not to long, and not to short.    

9-10-10

Today our work time was significantly cut by the irregular schedule, but we still got considerable work done. I Estimated that by hitting in the center of the hitting circle would give us better results. This is because more of the force would be put in the car and less into flinging the parts in the air. Our results are listed below: Distance 1) 1.45m, 2) 3.32, and 3) 3.86 (distance 3 was with center force).

We got the acceleration and velocity by plugging in the time initials, time finals, and distances, then we used the velocities to find the acceleration. We used the formulas v=d/t and a= vi-vf/t. We also did our first force diagram (we know we are behind, but will work hard and pull through) today. As the force diagam shows, the spring force needs to overcome the forces against it to move the mass into acceleration (F=ma).

9-9-10

Today we tested our methods more and identifyed the forces at work in our car. We realized that the car applied to all three of Newton's laws. It applied to newton's first law because it would not move unless moved by our propulsion system and it would not stop until the friction of the axles on the wheel and the air ressitance acted.It applied to the second law, F=ma, because when we took off some mass from the car, it went faster because less force was required. It applied to the third law because when the string is attatched , it pulls on the string with the same force that is put on it, causing it to turn and the springs are pushed just as they push the car. We estimate that finding these connections and changing the car accordingly will help us make the car better by at least 20%, meaning we might hit 6 or 7 meters on the long track because we will know why things worked or not. Our new measurements are Mass: 280g  Top distance travelled: 5.43m Time I:.37 Time F:5.54. This means that the velocity initial is 2.7 because 1 divided by .37 is 2.7, our velovity final is .98 because 5.43 divided by 5.54 is .98. To get these, we used the formula v=d/t. We got the acceleration measurements by using the formula a=vI-vf/t and found the answer to be .31 mps.

~Tanner

9-8-10

Today, we worked on our blueprints and many of our journal entries. We applied Newton's 2nd law to our fingers when typing our journal entries, as you have to have a certain amount of Mass and Acceleration of your fingers to have enough force of N to push down the keyboard's keys. Our blueprints are of our new model of car (an elongated shape that comes to a point at the tip), our turning system, (a big heavy "brick" of legos with something attached to the top of it that can turn), we would wrap the string we use all around it therefore making our car turn with the track (mattering on how long the string is), we also drew our propulsion system, it consisting of 3 springs (2 medium size and 1 small), 3 wheels and a long grey K'nex peice.

~ Tristan

9-3-10

Today we proved that our new propulsion system works, it traveling 5 meters in a total of 5 seconds and 14 miliseconds. Our estimation of the meters traveled was 4 meters, so we believe the car did excellent. The three variables of this experiment are mass being the controlled, spring force used being our independent variable and our dependent was the distance traveled. The force of our car was 119.33N and our car was 277.5 grams in total. In the making of this experiment we used Newton's 3rd, as our propulsion system is pushing springs together and using thier spring force to power our car. Newton's 3rd law states for every action their is an equal and opposite reaction.

~ Tristan

9-2-10

We are coming up with ideas for a new propulsion system, our current one obviously isnt good enough. We are still going to use springs because spring force is very powerful.

~Matt

9-1-10

Today we worked with other groups to try to improve the quality of our car. We moved a distance of about 1 cm about 1 sec, making our velocity .01 mps forward, and we could not find acceleration as we could not have a velocity initial. Obviously we need a change in plan for the propulsion, and we are thinking about taking two springs and three wheels connected by a long rod and then released for energy. Once again, this would apply to newtons third law because the same force being put into the springs should be put into the car. We also discussed other plans, but this one seems the best.

~Tanner