5.4.3.2.1...

  6 SECONDS, THATS ALL! Obviously we did not make it to 10 seconds. However we did manage to past yesterday when it was hard for us to get to 5 seconds. Basically our bottle was made of two different 2 liter bottles. We cut one of them in half and taped the bottom of it to our other bottle. We then added on two fins, these were different than yesterday. They were made out of manila folders and were bigger than our cardboard box ones. We also decided to make smaller fins to go on the top of our rocket. At home Amber had made a new parachute because our other one was to small. She also added a rubber band to make it more schock resistant. Finally we used a cone from when my dad used to coach soccer, it had some holes in it so we were wondering if it would work better or worse than our solid orange cone. We also added a weight onto the top of our nose cone to add some mass. When the cone fell so would the weight so that the rocket would be lighter when the parachute deployed. We did a couple launches and realized that we needed to change some things. For our final rocket we used the original base, the bottle and a half taped together, and our second parachute. However we changed the fins, the weight and nose cone. We took off the two smaller fins and cut the bigger fins because they were so large that it was actually harder for our rocket to get a lot of air. The weight on the nose cone did not seem to be working well so we moved it to the actual rocket. This also didn't seem to be helping so finally we just did not use it. We also decided against the cone with holes in it because the parachute didn't deploy because it would get caught in the holes, so we used the solid orange cone.

Our rocket!

   I think that what really helped us get to 6 seconds was our parachute. Although it did not always deploy at the right time when it did it added lots of seconds to our time. I feel that the reason we didn't get 10 seconds was because we were not able to get our rocket high enough. If it had gone higher the parachute would have deployed and therefore taken longer to come back to the ground. During this activity I learned a lot, not all about physics but a lot anyway. I learned that it is really hard to build a rocket, let alone to build one so that is stays in the air for 10 seconds. I also learned that parachutes are really important, they help your rocket stay in the air for longer and make the landing easier so that your rocket doesn't get busted every time you launch. Some physics related things I learned was that the water acts as fuel and therefore when the water runs out the rocket will stop accelerating. With that said it is important to launch your rocket before your water starts leaking out. Finally I learned that this is a super frustrating lab and some times you cannot always do perfectly.

Amber &I with our rocket and parachute!

Our rocket, parachute and cone!

It aint rocket science.

   Today we started to practice launching our modified rockets. My group decided that we were going to test after each thing we added to our bottle that way we could understand what helped and what did not. We started the day by cutting another bottle and taping it to our original bottle. We went and tested this, it was about 3 seconds, and we needed 5. We had our work cut out for us. Next we decided we needed to add some fins, because we had no construction-like paper we used a cardboard box. I cut two identical fins and placed them near the base of our rocket. We also felt that we would want a parachute so we took a longs bag and attached string to it. We then taped the string to the top of our rocket, we got a cone and placed it on top to make an aerodynamic nose cone. Our idea was that the cone would fall off in mid air so that the parachute could deploy and then have it take longer to have our rocket touch the ground. When we did this we were able to get 5 seconds. However for tomorrow we need ten seconds, so we got some new ideas. Our parachute needs to be bigger than just part of a longs bag, also we need to make our rocket have more mass. Hopefully after making these modifications the rocket will work tomorrow.

our rocket, minus the cone and parachute.

Unit 8: WERK IS GUUURL(:

   Today was so much fun. Finally we got to shoot off our bottle rockets. I am honestly small kine worried for tomorrow because our bottle rocket did not stay in the air for long at all. We need to have 5 seconds in the air, thank goodness we get to make some modifications. Today we also did a lab about power, or the amount of work per unit of time. In this picture below Amber and I are running towards the slip-in-slide. She was running faster than I was so her time was less. Her mass is also greater than mine and therefore her power was greater as well. An important equation that I learned today was that to find power starting with mass, distance and time you must first find force by multiplying mass and gravity. Then multiply that by distance to get work, finally dividing that by time to get power.

Unit 8: DO WORK SON!

   We are on to a new lesson, this one is about work and energy. In the physics world the term work is a little different then I thought it was going to be. Work is any change in energy, it equals the force multiplied by the distance, the units for work are called a joule. Like momentum there is also a Law of Conservation of Energy, it states that energy cannot be created or destroyed it will only change forms. To make matters even more confusing there are different types of energy. There is gravitational potential energy which is the energy an object has due to its position in a gravitational field. Then there is kinetic energy, that is the energy of motion. Finally there is Spring Potential Energy, this one is the most confusing. While learning about springs we learned about the elastic limit, or the most a spring can stretch before it is deformed. Lastly there is power or the rate at which work is done, and its units are called watts.

   This is a picture of my family at Alamoana beach. We had to stand there and hold up those boards, at somewhat of an awkward back angle, for quite some time before we finally got a nice picture. To me it felt like a lot of work because the board was heavy and it was not a comfortable position. However in the physics world I was doing no work, because I was not moving. If I had been carrying the board to go jump in the water then I would be doing work because I would be covering some distance.

Humpty Dumpty...sat on the third floor of bishop?

Today was our egg drop day, Brandon and I were partners and guess what...OURS SURVIVED! Our design was actually quite simple. It involved three car washing sponges, some fishing line, a circular sponge-like thing and a big bag of packing peanuts. We put the egg into the circular sponge-like thing then stuck it in the middle of the tree car washing sponges. We made a triangular shape and wrapped fishing line around them to hold it in place. Then we put this whole thing into a safeway bag full of packing peanuts then wrapped duct tape around the bag. Finally we put very small holes in the bottom of the bag so that air could go through the capsule. This is a drawing of our project.

I am not a good drawer.

I think that this worked because of physics, we were able to make the contact time longer therefore the force is less. We managed to make our design light so that it reached its terminal velocity faster. There were two forces acting on our capsule, these were weight or gravity and air friction. Here is a force diagram of our capsule.

Force Diagram

Plan of our capsule

Some things that we could have changed is the bag that we put it in. When the bag was being dropped some of the peanuts fell out. I do not think this really effected it but we could have sealed the bag better so it would be less clean up after. Also when it was falling the bag actually hit the railing. Basically I think that it worked best because we were able to use only soft items that would not damage our egg. By using soft items the weight of the capsule was less making the terminal velocity happen faster. One thing that confused me was that at the bottom it did bounce. When we did equations the bouncing always made the force more therefore when I saw it bounce I assumed that egg would have cracked. If I was to redo this I would make it so that the capsule would land with no bounce.

Final Product

Proud Brandon with our capsule.

The circular sponge-like thingy with our egg.

More Momentum!

HAPPY 4TH OF JULY Y'ALL(:
On this lovely independence day physics was all around us, even in the fireworks. Remember the problem we did in class about a rock breaking into 3 different pieces going 3 different ways? That is kinda what a firework is, it starts as one piece and when it reaches its highest point it explodes into lots and lots of little pieces that go all over the place. If it was possible to collect all the little pieces from a firework and calculate their momentum it would add up to the momentum from before it burst into lots of pieces. These pieces are all going in different directions, have different masses and different velocities. Because momentum equals mass times velocity if a piece has a large mass it will have a small velocity, and vice versa. Basically the "Law of Conservation of Momentum" is true because the amount of momentum that goes in equals the amount that comes out. So I hope that when everyone was watching the gorgeous fireworks they were thinking of how much it relates to physics, cause I was.

Unit 7: Momentum

Today we learned about momentum, it is funny that I couldn't even define it yet I have used this word for most of my life. The definition is a property of a moving body, and it is equal to the product of the body's mass and velocity. Momentum is a vector quantity and it's variable is "p". We also learned about a law called the "Law of Conservation of Momentum", this means that the momentum that goes in will be the same amount that comes out.
We did an activity that involved throwing water balloons and we found out that the best way to make them not break is to extend the contact time. By making the contact time longer it decreases the force on the balloon making it harder to break.
When I thought of this in real life the first thing that came to my head was my dad's keys. We don't just hand stuff to each other in my family, we throw things. My dad always throws me his keys and I used to just catch it and it would dig into my hang and hurt. Now I know to give with the keys and it doesn't hurt. This is because I am able to extend the contact time therefore making the force less and the amount the key digs into my skin is less.