In class today we wrapped up unit 6 and tomorrow we have our final exam for the 1st semester. In order to help us we're supposed to write a blog post about what we will take away or what we have learned so far. That way we know what to study when we can't remember things to put into our blog post. We also are supposed to write about the challenges of this semester / content of this semester.

What I will take away from Semester 1 physics. I learned so much this semester I dont know where to start. I guess mainly I will take away most of what we've learned, so far everything has kind of made sense. Each unit lead into the next which made it pretty easy to grasp and follow along with. The only thing i had trouble with was unit 5. The Soh-Cah-Toa thing didn't really make sense to me until like the day of the test when we reviewed/last minute teaching. Thank goodness I understood it because it was all over that test!

Today in class we also got to do a cool experiment to see how a pulley changes the direction of force. We used a long triangle thing that basically made a sled have 0 friction and it could be pulled by a little tiny screw. It was pretty cool and if you put your hand on the long triangle thing because it was blowing out air it kind of felt like you were petting a soft animal.

Unit 6

Today in class we learned about Newtons 2nd law, and motion. This unit will mostly be covering motion and forces, and more force diagrams. Newtons 2nd law is the Law of Motion, it  basically says that the acceleration of an object is directly proportional to the net force acting on that object, and inversely proportional to its mass. This can be put into an equation which is F = ma. F is the net force (all forces acting on the object added together), m is the bass and a is the acceleration of the object.

A force diagram is just a diagram that shows all the forces acting upon a single object. When drawing these you need to make sure you only draw forces and not things just sliding due to lack of friction. If the surface of what your object is sliding on has no friction or has friction it could effect your force diagram. Make sure to know if there is friction or not!!

An example of Newtons 2nd law is...

An elevator is moving up at a constant velocity of 2.5m/s, The man has a mass of 85kg.
Question:
What force does the floor exert on the man?
In order to find this out we will need to use the equation N=mg this translates to numbers as 85kg(9.8m/s^2)=833N
We now know that the elevator floor is putting a force of 833N on the man.

The reason I scorpion instead of sliding down easily and painlessly is because of friction. In this picture you can clearly see friction stopping me and thats kind of why I face plant. Twas very sucky.

Unit 5 Part 2

Today was AWESOME, we had one of the coolest/most fun activities I've ever done in school. We got to make a massive slip and slide about 35ft long. This slip and slide help to reduce our friction and thats why we were able to slide so far down. When I went down when it was dry i only slid, maybe 5 feet. This is because without water or soap the slip and slide is just like normal ground. Now with water and soap added this helped to reduce the amount of friction by a lot and thats why Jonas and Candace could slide all the way down! This wasn't the only cool thing we got to do today though. We also got to play with frisbee disc things that basically made the entire ground like an air hockey table. Most of them didn't work but a few did and those things were nuts! They would slide across the entire floor no problem. This is because they were reducing the amount of friction between the bottom of it and the floor by pushing air out of the bottom. Mr Blake said that at Kam they can do it across the entire gym floor which I thought was pretty cool!

Although this was very fun we also had to learn a great deal today in class and had our lab practical which was pretty confusing. The lab practical was on forces, friction and tension. Although we were adequately prepared the lab still confused me because we weren't allowed to see the spring scale so I kept doubting my equations and answers.

Interesting fact of the day:
If a bus and bicyclist collide the both hit each other with the same amount of force. Although the bus and bicyclist hit each other with the same amount of force the bus is to beast mode (it just has more mass) and will plow through the bicyclist.

This is Kelli playing with the cool air hockey puck fancy things that reduced friction, awesome.

Unit 5 - Part 1

Unit 5: 

Vector: A quantity that has both magnitude and direction.

So far in unit 5 we've only covered Vector Analysis and Newtons 1st law, the law of inertia. But before talking about Newton lets go over what Vector Analysis is. Vector analysis is being able to identify the Vector in a word problem and then based on that solve. There are different ways to solve Vectors, the easier way for me is the "Graphical Method". When adding two vectors using the Graphing Method you simply move vector B onto the tip of Vector A. Make sure that vector B's tail is on the tip of vector A's. This is if you have two positive vectors. If you have a negative and a positive vector you will take the TIP OF B and connect it to the TIP of A. Basically you just flip vector B around. 

Just a tip, a common vector is velocity.

Drawing of Graphical Method 

Problem: Suppose that there is a train moving south at a constant velocity and that velocity is represented by vector A. Now lets say that there is a strong north flying swarm/flock of seagulls that suicide it into the train to slow it down. The seagulls will be vector B.

Two positive vectors:

Vector A = +3.0u

---------->

Vector B = -2.0u

<-----

3.0u-2.0u

the answer (C) would be 1.0u

Diagram 

---------->

                  =        ---->

    <------

For Newtons Laws we have only learned the first one and that is the law of inertia, the law of inertia states.

"Objects in motion will tend to stay in motion, unless acted upon by an outside unbalanced force." This just means that you need a force that is unbalanced to move an object at rest. Simple :)

In Unit 4 so far we have had a lab practical and have a test this Monday. The lab was fairly easy, all we had to do was... Roll a ball down a ramp and through 2 speed laser magic time recording things. Basically they tell you how fast an object is going in m/s without having to make them one meter apart. Anyways we had to roll the ball through these to find the velocity then based on the height of the table where the lab was set up we had to calculate how far the ball would go before it smacked the floor. Again we have to use the set up

D
A
T
V
Vo

and majority of the time when finding how far the object will dravel we'll be using the equation D=1/2AT^2+VoT. This equation will pop up a lot during unit 2, 3 and 4 so get used to it! In unit 4 I have really learned how to use this equation well. I can pretty accurately tell you where your object will land :D

http://www.simhq.com/_air9/air_272d.html

Today in Unit 4 everything was basically the same as Unit 3, except a lot more complicated! Instead of us thinking in 1 dimension we had to think in 2 dimension. And well it blew my mind, although it was pretty easy to pick up after lunch. The calculations / equations are the same except instead of a simple
D
A
T
V
Vo

it's now

X  Y
  D
  A
  T
  V
  Vo

Meaning that we have double the amounts of calculations when we try to figure things out. Also instead of just thinking how fast something is going we have to calculate how fast something is going along with it's direction. A lot of it is very interesting. I learned that if you're on a rail cart going at 10m's and you launch a cannon ball, from a cannon pointed straight up on your cart. Because you and the cannonball are traveling at the same speed, the cannon ball will actually land back into the cannon. Probably killing you and whatever Panaraguan revolutionaries are with you.

http://www.vias.org/physics/bk1_08_01.html

Unit 3: In Unit 3 we went over Acceleration! I thought it was kind of cool that the because of the earths gravitational pull objects we drop accelerate at a rate of 10m/s^2. We also got to do super fun experiments like riding the danger board down a hill and having Matt skateboard down it! By reading the other classes blogs i realized that they also enjoyed Unit 3! I would have to say that although this unit was the hardest it was the most fun when it came to experiments! :)

This is Devon conducting the experiment which we based our lab practical on. This is called a picket fence i believe and the instrument basically shows us how fast it accelerates between the stripes. This experiment was easy but the test was kind of difficult. Thank goodness this fun / difficult unit is done!

Unit 2: In Unit 2 we went over graphing lines and how the slopes of these graphs could be changed into different graphs such as. Velocity vs Time and Distance vs Time. This unit was fairly easy and most of the lessons were straight forward. No hidden tricks or anything! :)

Unit 1: In Unit 1 we went over accuracy vs precision and scientific notation.

Accuracy is lets say you have 3 darts. You throw the darts at the bullseye and you hit it! all 3 times but they are spread out throughout the bullseye. This means that you're accurate but not precise.

Precision is lets say you have 3 darts. You throw the darts at the bullseye and you miss! All 3 times but they cluster together around the last ring on the board. You are precise for clustering the darts. But you have terrible accuracy and I wouldn't suggest you become a professional dart thrower.

Scientific notation is just taking big big big numbers and condensing them into an equation. For example 5,000,000 can be simplified to 5.0x10^6. This equation will total to 5,000,000 but it looks nicer and takes up less space. The way to do scientific notation is you just simplify. Move the decimal however many places you want to and count the numbers you took out. The numbers you took out will be whatever power of 10 you will have.

Video of me teaching my mom about Accuracy vs Precision and Scientific Notation.

In Unit 3 we learned about accelerations, graphing acceleration and about what Galileo theorized. We had a lot of exciting experiments in Unit 3. In Unit 3 all laws are the same as Unit 2.

Laws:
1) The slope of a position vs time graph is velocity.
2) The slops of a velocity vs time graph is acceleration.
3) The area under the 'cure' of the line on a graph is distance travelled.


For example today we were asked a question. If two balls (a tennis ball and a kickball) are dropped from the same height at the same time which will hit the ground first? I predicted that the lighter ball or the tennis ball would hit the ground first. I mean seeing that it's so much smaller and lighter surely it should drop first, right? Wrong! Both balls fell to the floor at the same time which really surprised me! It turns out that no matter what the object if they are dropped at the same time from the same height they will hit the ground at the same time! The reason is that the gravity of earth accelerates things at a rate of 10m/s^2. That means that each object accelerates at the same rate which causes them to both hit the ground at the same time. For Galileo to think about things like this such a long time ago he must've been a genius! Who also must've had lots of time if he could just sit around dropping objects.

(This is Mr Blake about to drop the two balls)

We also learned about different equations to figure out missing parts of information. These equations really help during word problems when they ask you to find the rate of acceleration but you're only given the time, distance and initial velocity.

Equations:
D= 1/2at^2 + v0t       We call this d,a,t
V= v0 + at                 We call this v,a,t
V^2= v0^2 + 2ad      And finally this is v,a,d

Acceleration= Change of velocity/time = m/s / s  = m/s^2

v0 or sometimes in other books vi is the original velocity
the normal v stands for ending velocity

All laws that applied to Unit 2 also apply to Unit 3.

Today was the first day of Unit 3 we learned a lot. There was so much information I thought for sure my brain would explode. We learned about Acceleration vs Time graphs and how to draw the proper line to show acceleration. We also learned about changing Distance vs Time or a Velocity vs Time into a Acceleration vs Time graph which was pretty interesting. We also learned three new equations to help you find extra details from a Acceleration vs Time graph. A neat fact is your body only feels accelerations.

During our class time we got to see acceleration in the real world we got to use the danger board from class and someones skateboard. We took them to the hill infront of Bingham and set up timers 5m apart from each other all the way down the hill. It was interesting to see that towards the end of the hill the speed at which the skateboard was travelling almost stopped increasing.

In the latest of unit 2 that we have learned, we learned about the different line shapes and how based on the slopes of these lines you know what their velocity is. If a line is facing downward on a position vs time graph you know that the the slope is negative and that the object is moving away from its starting point. We also learned about how to draw velocity vs time graphs and how a vertical line is impossible to make in our world.

This picture is a real life graph, if you observe closely and imagine. My stick (the wooden one) is a line on a position vs time graph you can see that it has a negative slope. This means that the line is going downwards as time progresses. 

This picture is a velocity vs time graph, if you can again imagine it. Look at the white stick it is perfectly vertical. In class today we learned that a vertical line is impossible to achieve because you're moving and not moving at the same time. Thus it can't ever be achieved in the outside/real/our world, it can be drawn and talked about but to physically make a graph with a line like this is impossible. Trippy isn't it? This is Jacob Sparks in the photo with the white stick.

In Unit 2 we learned about position vs time and difference between speed vs velocity. We also learned about Scalar quantity, Vector quantity, and also displacement vs distance. After all of that we learned about how velocity is equal to the change in distance over the change in time and this in other words is the slope. This is where i became very confused because when solving problems some of the slopes ended up being zero and I just can't think of slopes being zero so i'd keep doing the question over and over again. After awhile i realized that it was just a way of making the problems harder to solve. This is when it all kind of came together and i was able to start really banging problems out. Whoo

In unit one we learned about accuracy versus precision, graphing equations and what equation will cause what graph. We also learned about standard form and scientific notation. In unit one we covered very little but we went very in depth in our learning.

Accuracy versus precision: Accuracy is having one dart and hitting the dart board in the center. While precision is having lets say, ten darts and as you throw them they all hit roughly the same spot as the others. This means you're not accurate but you're precise, precision is basically consistency.

Learning about graph shapes and the algebraic representation of them was pretty interesting, i learned that in order for a line to be linear it had to have an equation of y=mx+b. I also learned that square roots can actually form graphs and if the graphed line were to keep going it would almost meet up but due to a certain law they never will.

We also learned that standard form is for example 4,000,000,000. This number is big and gross and ugly. In order for scientist to make things nicer and easier you simply cut it down to 4x10^9. This process is called scientific notation. It makes things much easier.

My name is Giovanni Kamo`i Borja, I was born in Honolulu Hawaii and currently am a Junior at Punahou School. My hobbies include Freediving, Bodysurfing, Hiking and Fishing. As for sports I am the varsity starter for wrestling at 215lbs. I was dominating my weight class last year but unfortunetly i suffered a season ending injury, but I'm ready for this year! I also play Lacrosse for Punahou, we have won 3 state championships in a row so far and I hope to make it 4!


As for science I'm not very smart my average grade for science classes has been a C+ or B- and I am not comfortable in science classes at all. Because i have had such negative results from this class i tend to not even enjoy going to it. I really hope that this summer changes that!


I am going into algebra 2 BCP, I took geometry last year and that was super challenging for me. Algebra is much easier in my opinion, I'm not very good with shapes either. Math although challenging for me is pretty fun because I've had teachers that have helped me so much and made math interesting for me. Because I have ADHD i get distracted very easily and have been down graded so much in classes because i can't always pay attention like other kids.


To be honest I just want to get science out of the way, I hate it so much all my teachers have been mean. And also it lowers my GPA and I don't even understand it, for example WHAT ARE MOLES I mean what the heck they're so complicated and it always changes when you do them. They are super challenging for me :(




This is me on the Lacrosse field, I am a dominant very aggressive player. I play defense and that's why I am holding such a long stick. The D-Pole is actually 6ft long thus giving me more range when hitting people or throwing stick checks. This was our championship game and everyone was going hardcore, in this picture you can see me hitting the two players in white jerseys. They ended up both being concussed and were taken out of the game. Like I said earlier I am a very aggressive player, if you get in between the ball and I you're done!