Quarter Two Review.

QUARTER TWO IS DONE...SAY WHAT?!
wow that went by very quickly. Cannot believe we are halfway done with the "school year". In quarter two we learned about projectile motion, forces in equilibrium and forces that accelerate.
   Projectile motion was basically doing kinematics twice, because we now had two axes. The vegas rule was introduced and my brain had started hurting after class. After a lot of practice I was able to understand the process.
  Next was forces in equilibrium. This meant that all the forces canceled each other out so the object did not move. We learned about free body diagrams and then my brain really started hurting. It took me a long time to understand forces and these were supposed to be easy.
  The harder ones were ones that dealt with acceleration. This happened when two opposing forces were not equal. For example if something is on a string and accelerating upwards that means that the tension force is greater than the downward facing weight force.

Here some boys are trying to move a pen by pulling on a paper underneath.

Unit 6. epic fail lab

Today we did a lab called the "Air Track Lab". It looked pretty cool because when you turned it on there was no friction, like an air hockey table. In the first part of the experiment we kept the force constant and changed the mass on the cart. This showed us that mass and acceleration have an inverse relationship. Part two was when we kept the mass constant and changed the force this showed us that force and acceleration are directly relative to each other.

http://img.ehowcdn.com/article-new/ehow/images/a08/aj/dd/physics-pulley-systems-grade-8-800x800.jpg

Unit 5&6...I think

Let's start with unit 5, the semester project says the Unit 5 is forces in equilibrium. Basically that means that the object is either not moving or is moving at a constant velocity. The forces that act on the object would cancel out making it not move, or have a constant velocity. Every object has a downward pull called a weight force, otherwise known as gravity. Therefore if this object is not moving downward it would either have an upward pull called tension or a upward push called normal force. To me this is all still a little murky and I don't completely understand it.


Next comes unit 6, forces in acceleration. This is when the forces do not cancel out and therefore it accelerates. For example if there is a ball that is accelerating upwards on a rope then the weight pull is less than the tension pull.

In this picture I am not moving, however there are forces acting upon me. One is gravity or weight force (that never turns off) this is pulling me towards the ground. Another is normal force pushing me away from the ground. Because I am not moving I can assume they are equal.

Newtons Laws

NEWTON'S THREE LAWS!


1.Objects in motion will stay in motions and objects at rest will stay at rest unless acted upon by an outside unbalanced force.
This pencil case is at rest, it will not move unless something moves it. For example if I poked it will my finger it would but it would not just move by itself.

2. F=ma

Force equals mass times acceleration. This is a very important equation, it also shows that force and acceleration are directly related and mass and acceleration are inversely related.

3. Between two interacting objects there is an equal and opposite reaction.

This was made clear in class when Jon and Dax were both sitting on chairs, Jon pushed Dax backward but he moved also moved back.

Unit 4. BLAST OFF!

ROCKETS ARE AWESOME! I love rockets, they are the coolest things on the planet. To bad nobodies hit Mr. Blake. In my mind I think he cheated, he knew the the air resistance would throw off our calculations so none of us would actually hit him. But those calculations were hard, we pretty much had to apply everything we learned and also had to get all the data ourselves. Normally in problems we will get how high it goes or what the speed it but for the rocket lab we had to figure it all out by ourselves. For me that was actually the challenging part, not really the calculations, to figure out what numbers go where. If we had all been given the data I think it would have taken us about 10 minutes not an hour. I do admit that shooting rockets is really fun and I was not really paying attention to most numbers I was just having fun setting off the rocket. I think friday was my favorite day so far this summer because it was all about this one lab, and taking a test, that wasn't so fun. It's amazing thinking about what we can do now that we know all this physics!

Our Rocket!

Anyone see the tiny dot in the sky, that is our rocket on super!

Unit 4. Projectile Motion

In unit three we learned about kinematics mostly just on one axis at a time. That seemed really easy and I was thinking how hard could this be, turns out, really hard. Today we learned about kinematics but using two axes. At first it was very confusing, although it is around us everyday the thought of something going forward or backward and down or up at the same time is very mind blowing. An example that we used in class is when Mr. Blake threw two pens. One he dropped straight down, he somewhat threw the other one forward. At first everyone thought that the one that went straight down would drop first but actually they landed at the same time. Next we learned about the "Vegas Rule", what happens in vegas stays in vegas. Except we changed it a little, now it was what happens on the x axis stays on the x axis and what happens on the y axis stays on the y axis. This rule applies because it tells us that even if the x axis is constant then the y axis can still be accelerating. One example that I thought of this surfing. You can be on a tiny wave, like the ones I attempt to ride, and be moving at a constant velocity then as I normally do you lose your balance and fall off the side of your board. For a split second before you hit the water you are actually moving both forward and down. I think I now understand how to figure things out even if they use both axes and hopefully I will remember it tomorrow for the test.

Quarter 1 Review.

In quarter one we have already gone through three lessons! Such a short time for so much information! In Unit one we started with pendulums. We learned that only the length of the pendulum will affect the period time. We also learned the names of the relationships of a few graphs, such as: no relation, direct, inverse, square, and square root. Finally we went over dimensional analysis problems. I believe this was all on the first day of summer school. On the second day we had our first test, this shocked me, we had only been in physics for a day and we already had to take a test!
Unit two was harder, now we were learning about kinematics. The first thing we learned was if someone asked us, "are you moving?" we are to answer, "relative to what?". We then went in to learn about scalar and vector quantities as well as distance, speed, velocity and displacement. At first everything seemed very confusing but when we added graphing for some reason it all made sense. There are three major rules to graphing, one, the slope of a position vs. time graph is velocity, two, the slope of a velocity vs. time graph is accelerations and three, the area under the curve of a velocity vs. time graph is displacement.
Finally unit three came along where we learned about acceleration. I think this unit was the most fun because we did the most interesting labs. First to really grasp acceleration we did the skateboard lab, next we played around with volleyballs and saw how they accelerated down our slanted table. What really got me confused about unit three were all the word problems and the new equations. However now that we have been working on it for a while I feel like I finally understand, now if only I can get through quarter two.

http://www.fordyceletter.com/media/2010/08/a_man_throwing_papers.jpg

Unit 3. acceleration.

Today in physics we did two labs. For the first one we had to roll a volleyball down a slant, we used our table, and record the motion. We then graphed it and saw that the more the ball rolled the faster it would get. From this we learned about Galileo and his ideas about gravity and acceleration. He basically said that if two items are dropped they will gain the same amount of speed in the same amount of time. We tested this by dropping a volleyball and tennis ball at the same time and they landed at the same time as well. However when we tried it with paper it didn't work because of the air pressure. The second lab we did also used the motion sensors. The goal was to throw a ball above the sensor and try to catch it at the same level. Our graphs showed that the ball moved fast, slow, stop, slow then fast again. We learned that earth's gravity is always pulling objects down. So technically when you are throwing a ball up it is getting slower because gravity is pulling it towards the ground, that is also why it speeds up as it is coming down.

This is from the first lab:

Unit 3. danger!

Today in physics we did a super dangerous lab. Actually not really, it could have been but instead it was lots of fun. In this lab we had a skateboard like object and we put it on the top of a hill then placed people every 5 meters to time. Everyone started their timers at the same time and would stop when the skateboarder passed them. When we went back in the classroom and graphed our data is was easy to see that as the skateboard went down the hill it was accelerating. The slope of the graph kept getting steeper meaning that there was acceleration. We also learned a bunch of new equations using velocity, acceleration, time and distance. At the end of class we were introduced to physics word problems. They hurt my brain! It was so hard to understand the format Mr. Blake wanted but finally after working hard at it I understand!

Unit 2. eeep test tomorrow

On Friday we did a very interesting lab. We used motion sensors and Logger Pro. Our task was to try and match different position vs. time and velocity vs. time graphs. After watching others try it seemed really easy, it was not. We held wooden boards in front of us so that the sensor would not pick up our heartbeat because that would through the whole experiment off. On the position vs. time graph it was easier because all the lines were connected so in my brain it was easy to understand what I needed to do to make my graph match. The velocity graph was more complicated because it involved sudden stopping and speeding up.

Unit 2 Kinematics

So far in Unit 2 I have learned that Kinematics is the study of motion. When people ask the question "Are you moving?" the correct answer is "In relation to what?". At first this made no sense, you are either moving or not, it's a simple question. Now it makes sense, if I am standing next to my dog and I start to walk backwards from my perspective it looks like my dog is moving and I am staying still. However my dog would think that she is staying still and I am moving. This unit we also have a lot of vocabulary, most are words that I already know but the definitions are more specific. A couple of new terms are scalar quantity and vector quantity. A scalar quantity has magnitude or muchness, a vector quantity has magnitude and direction.


I also learned a lot about graphing. So far there have been two types of graphs, position vs. time and velocity vs. time. The slope for position vs. time is velocity and the slope for velocity vs. time is acceleration. Finally the area under the curve of a velocity vs. time graph is displacement. In addition I have learned a couple equations. One is distance=average speed x time, and also average speed is total distance/total time.

This is a picture from the podium raceway in Kapolei. I went there last weekend and it was so much fun. Everyone starts at the same place, the origin, and race around a track. Eventually everyone ends at the same place they start therefore the displacement is zero but the distance is however many times you went around the track. 


picture: http://yaling.hawaii-aloha.com/upload/Image/podium_raceway_noa.jpg

Unit One Review

   This is a picture of a baby grandfather clock that I made. There is a pendulum inside that counts the seconds. Every grandfather clock I know has one and they all count seconds. My Tutu has a grandfather clock at her house that is about my height, however the pendulum is the same length as the one in this picture. The bottom is much bigger and so is the stick but it still counts the seconds. This is a great example of our pendulum lab because it shows that even if the pendulum has more mass as long as it is the same length then it will have the same period time. I never really thought about this as an actual pendulum but know that we have learned more about them I can understand why they still have the same period time.

Introduction

   Some information about myself is that I have been at Punahou since kindergarten. It is a part of me because my mom works here and so did my grandpa. I spend more time at school then I do at home or any other place. I used to play a billion sports but now I am just focusing on school. I love going to the beach and my favorite TV shows are Pretty Little Liars and Castle.

   From about 6th grade I hated science, to make it worse I was also horrible at it. However last year I found out I was actually good at chemistry. That confuses me because it uses a lot of math, and I'm not amazing at math either. This past year I was in geometry and because I took algebra freshman year I forgot most of it. But for some reason chemistry clicked in my mind and I was able to realize science is not that bad. Hopefully in this course I will be able to understand how physics relates to everyday life. Also to be honest I really just hope to pass and not have to take it during the year. 

   This picture I feel represents me because it is a picture of part of this island  and also the view from my house. I see this everyday and it reminds me how very lucky I am to live in such a beautiful place.