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What is "Physics?"
Physics has basically been the study of everything. So much of it has been applied to real everyday life and its been very interesting overall.
Did I love the class?
Well... I enjoyed the class a lot, but too much of anything can be a bad thing sometimes. Although the material was interesting and I seemed to be doing fairly well in the class, summer physics couldn't escape the nature of summer classes which tend to feel overwhelming towards the end.
What did i learn in physics?
I learned a lot in this relatively short class that I honestly think may not stick with me very much, considering I can barely recall what we did 3 weeks ago. One thing that I did learn that will stick with me in the future is that on rare occasions, it is possible for me to pay attention for longer than half an hour at a time. In many other classes, i often have a very difficult time paying attention, but in this class, almost all of the time during class, I was focused on what we were learning rather than playing with my phone or doing other things.
What did i like about the class? / what could be changed?
Again, the material was very interesting and kept my attention throughout the course, but ended up feeling compressed and tiring. This was really my biggest problem with the class which again, cant really change due to it being a summer class. i could ask for unrealistic things like making shorter days, more breaks, etc. but it would just hinder our learning and end up making the time that we did spend feel even more compressed. I would have also honestly rather have had a final semester exam than a project at the end, but thats really just my preference.

Unit 10 Part 2

Wow. I accidentally did my part 3 blog post over this one, rewriting the content of it. I love technology. Anyways, whats another 45 minutes of my life that I will never get back that I could have spent playing video games with my friends or going out to the mall or something. Well this time, I'm going to try and make this as quick as possible so that i can pout and fume in a corner about my useless mistake. A specular reflection is one that reflects light on a smooth surface such as a mirror, but a diffuse reflection takes all of the wavelengths and scatters them depending on the smoothness of the surface, reflecting the light into different directions. We did a demo yesterday on lasers and how in the air, we cant actually "see" the light, but by putting a haze into the air adding tiny little surfaces for the light to reflect off of, we could see the path of the lasers. We also learned that the three primary colors when mixing light are red, blue, and green which can be combined to make magenta, cyan, and yellow. When red light is shown on a white surface, it appears red because white objects reflect all frequencies of light. when a red light is put to a red surface, it appears red because that is the frequency that it reflects. when a red light is shown on a blue or green surface, it appears as "black" assuming there is absolutely no outside light because the blue or green surface wont reflect the color red and will just absorb the wave.

Unit 10 Part 3

Even though today was a "short" day, the material we learned was just as condensed as yesterday's. Today was all about refraction and lenses. In a reflection, we learned that the angle of incidence or the angle that the light makes from its origin to the surface, will be equal to the angle of reflection relative to the normal or perpendicular line relative to the surface. With refraction, that isnt the case. Depending on the object's index of refraction, it will change the angle when it changes its medium. When light enters a slower medium, it will bend more towards the normal, but when going from a slower medium to a faster one, it will bend away from the normal. the index of refraction is basically the ratio of the speed of light in a vacuum to the speed of light in the medium. One thing to keep in mind though, is that this can only happen to a certain extent or until the light reaches the "critical angle" where it ends up just entering the medium and reflecting off of the surfaces within the medium. This angle can be found by taking inverse sin of the ratio of the set of indices. We also touched a little on lenses, but i assume it will be covered more in depth tomorrow. One interesting thing we did learn was how glasses work. Over time, the lenses on our eyeballs can change shape which in turn changes where the focal point is. Someone who has perfect vision has the focal point on their lenses exactly on their retina. The lenses of my glasses change how light enters the lens on my eye, therefore changing the location of its focal point.

Unit 10 Part 1

Unit 10 is about light and colors. Today we learned so much about different types of light such as its velocity which is represented by c and is 300000000 m/s, that the light we can see is only a tiny fraction of the wide spectrum of different types of light, and many other things. the different types of electomagnetic waves are radio waves which range from 500kHz-1000MHz, microwaves which range from 10^9 - 10^11 Hz, Infrared that is 10^11 - 10^14, the visible spectrum which is the light we can see ranging only from 4x10^14 - 7x10^14 and the colors go in least to greatest frequency in the order of red, orange, yellow, green, blue, indigo, violet, ultraviolet which is 10^14 - 10^17, x-ray 10^17 - 10^19, and anything above 10^19th is considered gamma. One main idea we learned from today was that certain objects can be opaque to certain mediums (cannot penetrate) while others are transparent to the mediums (can penetrate) an example of this would be clouds. On a cloudy day, light and heat aren't passing through the clouds, while ultraviolet or UV waves are.

Unit 9 Part 2

In the second part of unit 9, we learned more about waves. We learned things such as the difference between reflection and refraction, dispersion, natural frequency, resonance, the speed of sound, superimposition, and much more. Reflection is when a wave basically goes back in the opposite direction it came from where as refraction is when the wave bends. Natural frequency is "the frequency and object wants to vibrate at" and when something resonates with it, it has the same frequency and increases amplitude. Sound is a longitudinal and that the speed of sound is around 345 m/s depending on the air.

Unit 9 Part 1

Unit 9 is about waves and sound. This unit hit us in the face straight away with a total of 30 new vocabulary words that seemed a little intimidating at first, but after about an hour of demonstrations and explanations, it became much easier. There are two types of waves called Transverse and Longitudinal waves. The difference between the two are very different. An example of a longitudinal wave would be the sound produced by my guitar in the picture below, where as me thrashing a chord would be an example of a transverse wave. When these two waves collide, they go straight through each other and keep the consistent amplitude (height of half of a wavelength) where as if two of the same type of wave collided, the result would be the sum of their wavelengths at their collision point. In a transverse wave, there are 3 important terms. the node which is the point at which the medium appears to not be moving, the wavelength which is the distance on the equilibrium point between 2 corresponding parts of the "loops," and there is the amplitude which is the distance from the point of equilibrium and the highest point on the "loop" which is called the anti-node.

Rocket Lab *Launch*

• Analysis questions
• What design features were included in your rocket design?
  - A nose cone, 4 triangular fins, an extension to the bottle, a parachute, weights in the nose cone. 
• What worked as planned?
  - Our rocket fired correctly and flew fairly high.
• What did not work as planned?
  - Our parachute didn't deploy due to the nose cone staying on the tip of the rocket. 
• Your launch conditions:
• psi at launch -
  - around 60psi
• Amount of water in bottle
  - about half way filled - 1000 ml
• What this project taught you:
• The physics learned
  - Things such as air resistance, kinetic and potential energy, center of gravity, aerodynamics, etc.
• the "other" things learned
  - I now know hate bottle rockets with a passion.
• Final thoughts
  - Our rocket launch was extremely disappointing due to more than half of the features of our rocket not working. Our parachute only worked once only after our rocket launch failed and it only flew about 6 feet into the air. Also during one of our launches, the rubber plug flew off of the bottle and gave us an amazing launch time of 0.3 seconds. After the first day of launching where we only had the cardboard fins, the fins had broken off many times which compelled us to put more glue on the next day. The second day of launching (today) our nose cone got destroyed by the water and impact from hitting the ground so we had to make a new one which didn't really work as well. Overall, this lab was tiring, depressing, and got me covered in mud and water at the end of it.

Rocket Lab

We started construction and test launches of our water bottle rockets today. My partner and i have so far chosen to add 4 fins each in the shape of a right triangle, and a parachute made of a trash bag and string. To our disappointment, after adding the 4 fins and the parachute, we wrapped the parachute a little to tightly on our first launch and it did not open when it was in the air causing our rocket to fly towards the ground and break 3 of the 4 fins off that sadly resulted in a launch time of a little over two seconds. After removing the fourth fin, we tried to wrap the parachute a little looser and launched it again. This time the parachute opened and resulted in a launch time of a little over 4 seconds. Although I am disappointed in our current results, we're slowly making progress and I hope to get a launch time of around 10 seconds tomorrow.

Unit 8 Part 2

In the second part of Unit 8, we learned more about the different types of energy and also learned about power. Power is the rate at which work is done and is measured in watts. We also used graphs to represent the distribution of total energy. In the first picture represented by my first graph, you can see that my friend jumping over my other friend has all of his energy in potential energy because he's at his maximum height and at that moment has a horizontal velocity of 0 m/s. in the second picture represented by the second graph, you can see that as hes is about to hit the ground which is a height of 0 meters, his potential energy is 0 because it has all become kinetic energy.

Unit 8 Part 1

For unit 8 today, we learned about different types of energy which are potential energy of gravity, potential energy of spring, kinetic energy, and work. Potential energy is the energy that a stationary object has relative to its height, mass, etc. and uses the formula "mgh." Potential energy of spring has the equation of "1/2 spring constant * d^2." Kinetic energy is energy of motion and uses the formula "1/2 m * v^2." All energy is conserved, therefore if an object at rest at a certain height has "x" joules of potential energy, when the object is about to hit the ground after falling from that height will have "x" joules of kinetic energy. The two pictures below represent the object at rest with "x" joules of potential energy and the same amount of kinetic energy as it reaches 0 meters.

Egg Drop Lab

For our egg drop capsule design, we used a bag filled with slightly crumpled paper, the egg was surrounded with a soft nylon foam like material. The nylon foam was used to cushion the egg in the case that it fell over after hitting the ground and was placed inside of our bag filled with crumpled paper. The crumpled paper was used to create a cushion of air that could still withstand the fall of the smaller inner capsule with the egg and foam which increased the contact time for when the bag hit the ground. We tried to make our capsule have a low mass so it would decrease the force that it took our capsule to stop when it brutally slammed into the ground. We also used rocks at the bottom of our capsule to attempt to stabilize our capsule during the fall. Here is a diagram i made trying to illustrate how our device worked.

Unit 7 Part 2

Continuing to learn about momentum, we went more in depth about impulse which is the change in momentum and can be represented by either the variable "j" or delta p. Having all of these values to keep track of has been extremely confusing for me and i always get a lot of them confused, especially because momentum and impulse are represented by variables that aren't the same as the first letter of the word such as v for velocity or d for distance. Since impulse is just the change in momentum, it was hard to grasp at first that in two different situations with constant variables except for contact time, the impulse will always remain the same, but the amount of average force per unit of time can differ varying the result oh say crashing into a wall with a contact time of .001 seconds and a giant pillow with a contact time of 3 seconds. We demonstrated this today by doing a water balloon toss and trying to move with the motion of the balloon being thrown to try and increase the contact time as much as possible and therefore decreasing the average force applied per second.

Unit 7 Part 1

Unit 7 so far has been about momentum and collisions. The variable "p" represents the value for momentum which has the unit of mass*velocity or kg m/s. The way that this relates to collisions is that momentum is conserved. When two objects collide, the amount of momentum at the beginning and end of the collision remains exactly the same. The way we tested this was using our air track to collect data of different scenarios of collisions and recorded the velocities, used that and the mass to find the momentum, and checked to see that the momentum was conserved supporting the "law of conservation of momentum."

Semester 1 Summary

So far, this course has honestly been tiring and at some times intense while at the same time being very intriguing. So much information has been packed into 3 long weeks that have felt like months. Generally speaking, we've only learned the basics of kinematics and forces, but 3 weeks ago I definitely wouldn't have been able to tell you how high a cliff is based on how long it takes to fall down, finding a distance based on the angle of trajectory, or even the now seemingly simple difference between velocity and speed. Although things were challenging quite often, it always kept me engaged and i can't remember a time where I wasn't either paying full attention or working on something. Besides the obvious challenges such as "I don't understand what the question is saying" and "We weren't learning this when I left to go to the bathroom 2 minutes ago," I can honestly say that I didn't have any problems whatsoever for these past 3 weeks. Overall, I have had a great time so far and anxiously look forward to the second semester.

Unit 6 Part 1

Unit 6 so far has been a continuation of what we learned at the end of unit 5. We're currently continuing the topics of forces and force diagrams with the equation "Fnet = ma" which means that the total amount of force is equal to the acceleration of the object multiplied by the mass. If given an example such as an elevator with a person inside of it moving at a constant rate, the floor of the elevator would be pushing up with the same force as your weight. This lesson, we learned about objects accelerating and therefore changing the value of the net force. This topic so far has been a little difficult because making the force diagrams confuses me a lot, but its getting easier as I practice the concept more.

Unit 5 Part 2

In part 2 of Unit 5, we learned about forces. For objects at equilibrium which means that the object is not accelerating, what ever force is being applied to the object, theres an equal and opposite force being applied. Using examples such as a desk being pulled in one direction, we could find the force of friction acting in the opposite direction based on how hard you're pulling the desk. We also learned about how important the force of friction is. In the pictures below, you can see that the first picture shows how with a lot of friction, it makes it difficult to slide across the surface, but in the second picture, we see that by adding soap and water, we reduce friction making it easier to slide across the surface.

Unit 5 part 1

We began unit 5 today and focused the day mainly on vectors in two dimensions. A vector can be defined basically as a quantity with magnitude and direction. They can be illustrated on a piece of paper as a line with a starting point and an arrow. Today, we learned that the sum of two vectors would be the displacement of the distances on a two dimensional surface. We practiced adding vectors on the x and y axes but then moved on the the much more complicated diagonal vectors. We learned to add these vectors by making a right triangle for each diagonal vector and turning them into the hypotenuse for a right triangle. We then found the values for the opposite and adjacent sides of the triangle(s) and found the sum of the x and y values of the axes to be used to make another right triangle. That last set of vectors will form a right triangle where the hypotenuse of that triangle would be the final answer along with angle (data)

Unit 4 Part 2

In the second part of unit 4 we began to learn about angles of trajectory. Using what we learned from part one, we used trigonometry when we were given the initial velocity (hypotenuse) to find the vertical (opposite leg) velocity and horizontal (adjacent leg) velocity. In the picture below, we launched a n air powered rocket into the air and measured its muzzle or initial velocity. We then used that and an angle to predict approximately where the rocket would land. Although our rocket didn't hit its target due to some technical difficulties with our base, i was surprised to see how accurate some of the other student's calculations were.

Unit 4 part 1

Today we began unit 4. the first part of unit 4 has been basically about how far objects travel when traveling along the x axis at a constant velocity. We learned that the x and y axes are completely independence from each other disregarding time. For example, my picture was of when Mr. Blake explained that when a pen is dropped and a pen is thrown horizontally, gravity has the same acceleration on both objects meaning that they would hit the ground at the same time but land in different places. Using this information, we then learned how to predict about where something would land depending on things like height from the ground, initial velocity, etc using the equations we leaned in the previous unit.

Unit 3 Summary

Unit 3 was focused mainly on these three equations:

d = ½ at^2 + VoT

V = Vo + at

V^2 = Vo^2 + 2ad

These equations were basically used to help us figure out the values of unknown variables such as figuring out the height of a cliff when given the time it takes to fall down and the acceleration of gravity.

Additionally to that, we learned the relationships between graphs displaying data like position versus time, velocity versus time, and acceleration versus time. These graphs helped us apply our equations to real life situations such as balls falling, cars increasing speed, etc.

Overall, Unit 3 was very interesting and challenging because of a lot of technical things such as making mathematical errors in calculations. The most challenging part for me was keeping track of which direction the acceleration was working in. For example, if a ball was thrown up, gravity is accelerating it down but the value of gravity can change between 9.8 m/s^2 to -9.8 m/s^2 depending on whether or not you wanted the cliff to be x meters high or –x meters high.

Unit 3 part 2

In the second part of unit 3, we began using much more of the different types of equations to find unknown variables such as acceleration, average velocity, etc. Using d=at^2/2 + VoT (nicknamed DAT) V=Vo +at (VAT) and V^2=Vo2 + 2ad (VAD) we learned how to plug in our data to solve for different problems such as the height of a cliff that takes 6 seconds to fall from. Given the variables a for acceleration (9.8m/s^2 or the force of gravity) t for time which was 6, and an initial velocity (Vo) of 0, we could plug in the numbers

d=(9.8m/s^2)(6sec^2)/2+0 where d (distance) would equal 176.4 meters.

we could also use this to find the velocity of when its about to hit the ground using

V^2 = 2(9.8m/s^2)(176.4m) where the velocity would be 58.8m/s.

once we learn how to factor in things such as air resistance, i feel like this lesson could very much be applied to everyday usage.

Unit 3 Part 1

Today, we finished Unit 2 and began Unit 3. Unit 3 has started off as a continuation of kinematics like the previous 2 units but this time contains "acceleration versus time" graphs. We are now learning the full relationships between position versus time, velocity versus time, and acceleration versus time. Acceleration is defined as "any change in velocity" changing my whole perspective on the concept of acceleration. This means that slowing down, increasing speed, and even changing directions ca be defined as acceleration. In the activity we did today, we took two different types of wheeled objects: a board with wheels and a skateboard as shown in the picture below. We then positioned timers across as 45 meter sloped straightaway and graphed the data for 9 different positions going down the hill giving us an exponential graph shape.

Unit 2 part 2

In part 2 of unit 2, we continued kinematics. This time instead of a "Position Versus Time" graph, we used a "Velocity Versus Time" graph. We learned 2 very important rules when dealing with velocity versus time graphs which were that the curve of a velocity versus time graph would show acceleration and that the areas under the curve are the distances traveled over the relative time. To show this, we did a lab involving a distance sensor (shown in the picture below) where we tried to match different shapes on a position versus time graph and then created a velocity versus time graphs to accompany them.

Unit 2

Unit 2 was all about Kinematics which is the study of motion. Today we did the "Physics Olympics" lab which compared the velocities of different activities such as running, walking and jogging. Using our data, we made a graph where the independent variable (time) showed a direct relationship with the dependent variable (distance traveled) for all 4 activities. Then, we learned how to find the average velocity which was the total distance traveled (per activity) divided by the total time elapsed of the same activity which gave us the slope of the line (average velocity) in meters per second. Doing this lab demonstrated the applications of the formula for velocity and vectors. Once we better grasped the ideas of going in straight lines which on a graph would create a positive slope and therefore a positive velocity, we then added in things like change in velocity, immediate velocity, and negative velocity which was essentially going in the opposite direction. This graph shows our data from the lab we did in class.

Physics Unit 1

In unit 1, we learned about the different types of relationships between dependent and independent variables based on the shapes of a graph, the algebraic equations to go along with them, how to use scientific notation, and dimensional analysis. In the first part of unit 1, we learned how to record data correctly on a graph (differentiating between the independent variable which would be the x axis and the dependent variable which would be the y axis) and how to use the equations based on the shape of the graph to predict the value of the dependent variable based on the results of previous data. in the second part of unit one, we practiced the use of scientific notation and then applied it to dimensional analysis so that it would be easier to convert and visualize numbers with a large amount of digits. I would have chosen to take a picture of the "Pendulum Lab" that we did during class to represent unit 1 as it was a very important lab in aiding our understanding of the different types of graphs and relationships between variables, but i failed to remember to take a picture so I chose to substitute it with a picture of one of our graphs that we made in the lab. One of the most important things i learned in this lab was that many factors can come into play causing our data to differ from what is considered "correct" and that having a larger amount of data would give us a better understanding of the relationship of our variables.

Letter and Picture of Introduction

My name is Brent Tokumi, i live in Ewa, I'm 15 years old, my birthday is July 16th 1997, and I'm an upcoming junior. I've been attending Punahou School since I was in 7th grade and it has been an incredible life-changing experience. My hobbies include gaming and playing the guitar. I personally don't consider myself one of the best students because i tend to have a lack of motivation to accomplish tasks such as homework and studying for test which is related to a lot of what I want to accomplish in this course. The results of my poor study habits this past year has given me motivation to try to start studying harder and trying to learn more in my classes. So far in high school, i have only taken regular biology and chemistry and i have finished algebra 1 and geometry. My picture contains a few of the things i use to record music (except for the computer because i have my own but was using the school issued computer) and it best represents me because its my favorite activity in the world when i have good ideas and has brought me together with a couple of my best friends.