What I Learned From First Semester...

I can't believe that first semester has gone by so fast. So this is what I've learned:
Blake and Da Freitas have some crazy adventures.
Jose and Pierre are Panaraguan (sp?) revolutionaries, but they died. :(
Singing songs is a good way to learn physics, especially if it's Freitas on guitar.
Calculator= spaceship
Bored is spelled two different ways: bored and board.
Sheila is an Amazon, and piranha-men don't like her.
We go through a lot of SPAM and Nutter Butters in this class.
Da Freitas has an Ozone-Mobile, and it's kinda massive.
There are rainbows that marbles can drive on.
Fig Newtons are delicious.
Mass is not weight.
If a fly and a bus collide, it is the same force for both of them.
Batman and Chuck Norris are physicists.
There are a lot of unknown planets out there that have different gravities other than earth.
"Earth" is spelled "URTH"
Mr. Blake is secretly a Jamaican man "Da Whole Ting."
He also had a sensei that called him "Bureku-san" and taught him the secret "Bureku technique."
We like to do problems with cars, trains, boats, and boxes in them.
Roller coasters are really fun!
Pulleys secretly have one string, so one string = one tension.
Bowling ball pendulums can't hurt you if you let them go... as long as you don't PUSH them.
Mr. Blake can swing on a bowling ball pendulum.
A lot of kids like to play Tetris Battle during class.
I sit in the back row and sometimes it's hard to see the board.
You shouldn't procrastinate on your PAs— even though they're due in a week, you somehow put them off til the night before.
Keana and I eat some good snacks: swedish fish, cheetos, fruit, chocolate, etc.
Austin draws a lot in class.
Mr. Blake is also a DJ and Konia 209 is a club.
You should stand when Mr. Freitas enters the room and tell him "Good morning."
There are a lot of kinematics equations to remember and I still haven't memorized them all.
This class is the best physics class... I feel so lucky! :)

Energy

So this week's topic is ENERGY. The first thing we learned about energy is that it involves work ("DO WORK, SON"), but not the kind of work you might be thinking about. Work is the average force multiplied by the length or distance an object is pushed or pulled. Work comes in *Joules*, which are equivalent to Newton x mass. We learned about the law of Conservation of Energy, which is basically the same thing as Conservation of Momentum: energy can neither be created nor destroyed, it only changes forms. Energy is also a SCALAR, which means that it does not depend on direction, just magnitude (no negatives found here!) There are two kinds of energies; potential energy and kinetic energy. Potential energy is the energy in a still object (equivalent to the product of mass, gravity, and height). Kinetic energy, on the other hand, is the energy of motion (equivalent to the product of 1/2 mass and velocity squared). We are going to be doing a lab on Monday, so we'll literally get to see energy in motion.

Egg Drop- part 2

Hi, so guess what??? Our egg drop device was a SUCCESS! Keana and I (aka the Peruvian Eskimos) had a great day on Wednesday. Watch the video above for more details. Keana dropped it over the side of 'Akahi (about 3 1/2 stories tall) and I video'd its' fall. We did have to make a minor change, however: instead of stuffing the box with cotton, we used crumpled up (UNUSED) toilet paper. It did not matter— the device still did its job to our satisfaction. I was so happy not to hear a sickening thud and the squelch of a broken egg coming from our device, like it did to some other groups. However, we did have to do it again because the first time we dropped our device, it kind of hit a bush. That means that our egg survived TWICE :). All of the groups in our class had great ideas for egg drop devices: one group had a stack of sponges that encased the egg and was secured by rubber bands, another had aerodynamic design that would allow the egg to land safely, and yet another was a simple box filled with lots and lots of packing peanuts and filler. No two groups had the same design, so it was interesting to see how most of them worked. There was actually nothing I would have changed about our design... it was successful, so why change what already works?

Egg Drops, Impulse, Momenta, and other delicious topics

So this week we worked on creating a device that could contain an egg and deposit it safely (NO CRACKS) when dropped from 3 1/2 stories ('Akahi). We'll be testing these on Wednesday. So, I spent my period 4 with Keana making this device... how did we do ours? We built a 20cm x 15cm x 15cm box from styrofoam board in the SPC. In order to increase contact time and hopefully give the egg cushioning, we plan to slide the egg in a nylon stocking and knot the other end so it does not move around. Then we will fill the rest of the box with cotton, then tape the box shut and drop it over the edge. Although it would be wise to build a crushable box (to prevent elastic collision), we did not because we wanted the box to be stable in order to support our egg. We figured the cushioning we'd provide would suffice. Hopefully it works... tune in next week so I can tell you if it worked or not!

Learning Impulse and Momentum Is A Piece of Cake

Impulse can be defined as the 'change in momentum', or the average force multiplied by change in time. Impulse is a vector, just like momentum, and uses the same units (kg m/s). Let's work on finding the impulse in this problem. A 0.015 kg cake (like the one I have shown above) is thrown into the wall with a speed of 100 m/s. If the cake miraculously doesn't crumble and instead bounces back with a speed of 80 m/s, what is the impulse?

Well, first, we'd find the momentum. P=mv is P=.015 kg *100 m/s = 1.5 kg m/s. Then, P= .015 kg * 80 m/s = 1.2 kg m/s. When those two momenta are added together, you get 2.7 kg m/s, which is the change in momentum, or IMPULSE. And that, my friend, is the easiest way to have your cake and eat it, too. Although I'm not too sure why you'd throw that cake to begin with...

Momentum (or what I think it might be)

This week we will be talking about linear momentum and collisions. So here is what I think momentum is, straight off the bat, before we get into the real deal. I think momentum is the force of an object in motion— like a pendulum or that Chinese junk ship that Johnny Depp overturned in the third Pirates of the Caribbean movie. Momentum seems like such a loaded word: I am not sure what the most accurate definition of it would be, but it seems to be that momentum would have to do with both magnitude and direction. An example of momentum could be the force (?) behind the ball in a golf tournament, or the motion in a washing machine, right? I'm not too sure... this is just what I think so far, but I'm pretty sure momentum has to do with that sort of thing. We'll figure that out this week.

Maybe my sister is in momentum...? If she is moving with magnitude and direction...

Newton's Second Law of Motion

So this week we did a lab regarding Newton's Second Law of Motion, which states that the acceleration of an object is directly proportional to the force (or net force) on an object. However, the acceleration of an object is an inverse of the mass. The lab we did proved that when we did separate trials of differing mass on the cart vs the hanging mass. The changing force had a direct relationship, while the changing mass had an inverse relationship. So today's post has a picture of my dog, who is proving this rule with the force of touch on her and the acceleration of the wagging of her tail. The more *and harder* you push her or pet her, the more her tail accelerates. She's very light, with little mass, so it's easier for her to accelerate in comparison to a larger, thicker dog.

Free-Body Diagrams

Last week I gave you an introduction to forces and examples of what they do. So today I'm going to show you how to draw a free-body diagram based on a given situation. In the photo above, my friends are on an upward incline (a hill.) Therefore, there are three forces acting on them at any given time— mg (weight), normal force, and friction (keeping them on the hill.) To draw this, you would do this:

This shows that my friends are on the hill and are staying there due to three kinds of forces. I didn't know that free-body diagrams would help me to understand how to do my PA homework problems, but they really do! They also work with other objects, like cars, cartoon characters, balls, rocks, boxes, and Nutter Butters.

Forces

This week we learned about forces... we've moved on from kinematics! (Cue applause here.) We learned that a force is defined as a push or pull. There are two kinds of forces— contact forces, and 'at a distance' forces. Contact forces are caused by contact between 2 objects. You might be thinking, "So these objects are moving." WRONG! Not necessarily. Contact forces don't necessarily cause movement. In fact, contact forces could be just as simple as me and my friend putting our arms around each other for a picture, like in the photo above. 'At a distance' forces are forces that push and pull on objects without touching them. One of the most obvious of these forces is gravity. (SOMETHING FROM KINEMATICS— Gravity= 9.8 m/s2.) These are balanced forces. However, there are also unbalanced forces, also known as net forces. These forces are those that cause an acceleration of an object. A good example of this is when you push a bowling ball down a lane. We're going to be doing a lot with these forces— we'll be implementing them into Newton's First Law of Motion— objects in motion will tend to stay in motion unless acted upon by an outside, unbalanced, force. That's like when you push a person off a cliff and they continue to fall until a spaceship with a scoop net saves them and stops their fall.

Quarter 1 Extra Credit

My mom comments on the blog...

Adding Up The Vectors Graphically or Component-ly

So this week we learned about adding vectors graphically and using the component method (Bureku technique). This is a picture of me flying above Kailua (the Mokuluas are in the background). And NO, it's not Photoshopped. Pinky promise.

So if I am flying 300m north, then 400m east, how can I find the resulting vector? I can find it using the graphical method: creating a scale (100m=1cm in a drawing, etc) and drawing and measuring my distance, then creating a separate resulting vector that happens to be my HYPOTENUSE of the two original vectors. Then, I can measure the resulting vector and convert it. (I would get 500m, by the way.) Or you could use the component method, which involves going in and taking the sin and cos of the resulting triangle in order to solve for the hypotenuse.

But either way, it doesn't change the fact that I am FLYING! :) Yay...

Vectors

So this weekend's topic is VECTORS. (Think of Despicable Me...) Vector quantities have both magnitude and direction. A vector is represented by any one of the two arrows I am holding in my picture. I used arrows because vectors are graphically represented by arrows: the length of the arrow represents the magnitude of the vector. You connect vectors head to tail, so you add the tail of the second vector to the head of the first vector, like how I do in my photo. The resulting vector (the sum of the two vectors) is called the resultant. The converse is also true: any vector can be broken up into two or more other vectors (applying the ブレクrule, not the フレイタス rule). And as Mr. Freitas taught us via music on Friday, the hypotenuse of a right triangle represents the sum of the two vectors (the opposite side and the adjacent side). Now let's hear him belt out a parody of (I've Had) The Time Of My Life... just kidding...

Kinematics on the Track

This is a picture of me running the 1500m at Punahou for a JV meet this past track season. YAY! (However, I did not come in first. [insert sad face here].) Anyway, this has to do with our lovely kinematics unit because when I run (or as a matter of fact, when ANYONE runs), we use velocity, speed and acceleration! Speed is just a part of velocity, which is a vector, and my velocity during this particular race was 30m/s (JUST JOKING. I wish.) But seriously, velocity is important because that's what makes or breaks your time. You could use the VAT equation (V=Vo+AT) to determine your final velocity based on your initial velocity (normally zero) once you have your time and acceleration. And acceleration is what lets you go past that Punahou pack (except for Elli, who's too much of a speed star) so you can come in 4th or 5th and still look beautiful for your team. So, if you want to go running with me later, join track! :) You'll be a living example of physics in motion AND you'll have nice legs.

Introduction

Hi, Nikki here. I'm a late addition to period 4 and I'm happy to be here. :) I'm also currently in Pre-Calculus so if anyone else is, yay! Maybe we can help each other. As for my other sciences, I took BSCS Biology freshman year and Honors Chemistry sophomore year. I hope to obtain a better understanding of what physics is and how I can apply it to my life; I would really like to have a good understanding of other sciences besides biology.

I'm a junior who likes to be involved in EVERYTHING. I run varsity cross-country and track (1500m and 3000m) and attempt to balance my hectic life with a good dose of reading, songwriting, art, and travel. I like to run run run run run run run run run run run run run run run run run run run run run run run... yeah, if you haven't noticed, I enjoy running.

About this picture: I took this picture on Independence Day this summer. This represents me because I am independent and I felt very at peace with myself when this was taken. I also really like wearing the color red: it's a bold color that makes me feel happy. Another thing about this picture is that I am in my natural element: the great outdoors!

Oh, and one last thing: The title of this blog is a reference to an inside joke I share with Keana... it's kind of about ditzy girls (please don't think that's me, cause it isn't most of the time) but it's also about when I get asked questions (sometimes). See example below.

Person: Um, hi, I'm in (fill in class here)?

Me: ...Yeah?

Person: So, like, I heard you're in (class) too. Can you help me with (fill in the blank here)? 'kay thanks. Bye.

Me: ...Um...