Reflection

After performing the tests in school, I would say that the mousetrap car was quite successful. It traveled 29 tiles, which compared to some other groups was exceptional. What made the car work, was the force being used. The mousetrap held a lot of potential energy, specially in the spring part. It was also well put together. The CD's were glued into place and helped the car stay on a straight path. This project was overall a great way to show Newton's three laws. If I were to do this project again, there a few things I would have done differently. One, is not wait till the last minute. Although, this didn't negatively affect our project, it did rush us through the process. Another thing I would have done differently is glue down the axle holders (pen ink backs) properly. Even though it didn't affect the car's performance, the axle holders got loose during the testing. The reasons for this error was not applying enough glue on the car. Some further investigation I would do is research more on the balloon car and rubber band car. I could also test them by created a small model. I would also go through the mousetrap car's design until it was perfected. 

The Final Car

Test #3

Hypothesis: If a balloon is used as a rubber band around the wheels (CD's), then there will be greater friction

Procedure:

1. Cut top and bottom of balloon off
2. Cut what's remaining of the balloon in half
3. Stretch "rubber band" around each wheel (CD)
4. Repeat steps 1-3 for other set of wheels

Results:

When the "rubber bands" were put onto the CD's, the vehicles acceleration slowed down. Also, a forward force was necessary to get the car moving. The distance covered by the vehicle also decreased. 

Conclusion:

While the rubber band did indeed create friction, it caused the vehicle to slow down excessively. The hypothesis was proven correct, however the balloon rubber bands had a negative impact on the car. This leads to the conclusion of not using the balloon rubber bands on the wheels (CD's). 

Test #2

Hypothesis: If CD's are used as wheels, then the vehicle will follow a straight path

Procedure:

1. Insert pen through 2 CD's
2. Hot glue the CD's to each side of the pen evenly
3. Glue pen and CD's (wheels and axles) to vehicle
4. Repeat steps 1-3 for other set of wheels

Results:

When the car was released, the CD's allowed the vehicle to move in a straight, steady path. It also helped the car move faster and smoother. 

Conclusion:

The hypothesis was proven correct. One of the rules for this assignment states that the vehicle must stay in a 2 tile wide path. Using CD's will be an advantage since the CD's allow the car to move in a straight path. Overall, it had a positive impact on the vehicle leading to the conclusion of using CD's as wheels. 

Test #1

Hypothesis: If thread is used to pull back the hanger attached to the mouse trap, then it will unwind at an even pace

Procedure:

1. Cut an appropriate sized (in length) piece of thread
2. Tie thread through the hook attached to the hanger
3. Pull back thread and attach to axle
4. Wind the axle back
5. Let go of axle

Results:

As the thread was released, it unwinded slowly. Also, as it was unwinding the thread got tangled and slowed the car down.

Conclusion:

The results showed that the hypothesis was incorrect. The thread did not unwind at an even pace but rather got tangled and slowed the car down. The acceleration was negatively impacted overall by the thread. This leads to the conclusion of using fishing wire instead of thread. 

Final Design:

The final design used was based off of design #3. After thinking through the pros and cons, design #3 seemed to be the one that would work. It used both kinetic and potential energy in the spring and arm of mousetrap. Not only that, but it had a strong base with wheels that were guaranteed to lead a straight path. After performing a few tests, some adjustments were made. Such as using fishing wire to provide a strong hold on the hanger.  Out of all the tests performed, the vehicle goes a distance further than necessary and stays in a 2 tile wide path. All the rules are followed and used. 

What was done?

To make the car, 3 paint sticks were overlapped on each other. Two parallel to each other and the last one broken in half in the middle of the two. Then pens were put in between CD's as wheels and axles. These were glued to both side of the paint sticks base. After this, a mouse trap (cut and adjusted) was glued into the middle of the vehicle. Attached to this was a piece of a hanger that had a hook attached at the end of it. From this hook, hung a piece of fishing line that extended the length of the vehicle. This line was then pulled back bring the hanger with it towards the back of the car. The fishing line was winded up on the back axle of the car over and over. When this was released, the car accelerated in a straight path at a steady rate. 

Design #3- Mouse Trap Car

Pros & Cons:

Pros-

• Will follow a straight path (wheels are CD's)
• Fishing line is sturdy (durable; won't break)
• Base is strong and sturdy (paint stirring sticks)
• Strong source on energy (mousetrap) 
• Potential energy in spring (of mousetrap)
• Kinetic energy as arm moves (of mousetrap)

Cons-  

• Hanger can snap
• Materials were hard to adjust (mousetrap, hanger, paint sticks)
• Many different materials needed 
• Long building process