Summary of Quarter 2

Units 4 through 6 were focused more on motion in the real world, situations we encounter in our every day lives. In Unit 4 we learned about projectile motion, which is motion in the horizontal direction as well as the vertical direction simultaneously. In Unit 5, we learned about forces in equilibrium, which are the forces acting upon objects that are either stationary or moving at a constant velocity. In the next unit, Unit 6, we furthered our learning about forces, but this time we learned about forces that accelerate. (Newton's 2^nd Law of motion) This was more complicated than the last unit because this time we were learning about the forces acting upon objects that are accelerating. These three units collectively have helped me to understand motion in a real-world, practical way.

Unit 6

Today's lessons were really centered on Newton's second law of motion – force is equal to mass times acceleration, or "F=ma". This unit is structured around word problems, and many of them involve day-to-day situations such as acceleration of cars and elevators or pulleys. In class we did many activities and problems using pulleys. We learned that the larger the mass of the object attached to the pulley, the faster it will roll down when attached to a string. This got me thinking about free weights. I used to just think of weights as heavy objects to lift, but I never thought about the reasoning behind it. I realize now that the heavier the mass, the more Newtons of force you need to apply in order to overcome the weight force acting on the weight to the ground. Therefore each time you lift the weight, you need to apply more normal (applied) force than the weight force. Thinking about weights in a mathematical way helped me to understand why heavier weights were harder to lift.

Unit 5 cont.

In class today, we learned about free body diagrams. At first, they were really confusing to grasp and understand, but after doing a couple practice problems, I finally started to get it. It was hard to wrap my head around the concept that at any given time there are forces acting upon every object. For example, if you are just sitting still, you may think that you aren’t under any forces because you are not moving at all.  But even when you are just sitting in a chair, there are two forces acting upon you, yet they're balanced so you don’t move. There is normal force that is pulling you up because of the direct contact between you and the chair. Simultaneously, there is also weight force acting upon you, pulling you down with gravity. That's why it was hard for me to understand how one object could have 4 forces acting upon it at once. But going through today's lesson, I realize that even though an object may not be moving, that doesn’t mean that there are no forces involved – it just means that the forces are balanced and therefore aren’t apparent with movement.

Unit 5

Today in class, we learned about Newton's first three laws of Physics.

1: An object at rest will stay at rest and an object in motion will stay in motion unless acted upon by an outside, unbalanced force.

2: Force equals mass times acceleration.

3: If two bodies exert force on each other, the two objects will move with the same magnitude, yet in the opposite direction.

In order to learn and understand Newton's first law of physics, we recreated the tablecloth trick where you pull the paper out from under the pen super fast so the pen stays standing. This works as well with rugs and furniture. At home, I tried to pull the rug out from under a chair but it was super easy to keep the chair standing. This got me wondering – I know all objects that are at rest will tend to stay at rest, but is the amount of force needed to bring an object to motion after its been at rest based oan its mass?

Unit 4 cont.

Today in class we did a fun activity outside. We used our projectile motion formulas to predict where the rocket would land. Our calculations were accurate, but our trials never hit our target (Mr. Blake). This is because of a mix of outside forces such as air resistance, wind, and air friction. This makes me think of the football, as the rocket activity was similar to the throw of a football. When the quarterback begins a play, he chooses a player he wants to pass the ball to. He has to calculate his angle of release (how high he throws the ball), the velocity (how fast he throws the ball), and his distance (how far away the player is). So although it may not be written down on paper, the quarterback is calculating all of these factors in order to execute the perfect pass.

Unit 4

Today we learned about projectile motion as unit 4. It's cumulative of everything we have learned up until now, as projectile motion is movement that goes vertically as well as horizontally. Learning about projectile motion has especially shed some light on the physics aspect of ball sports. I used to play volleyball and this unit made me think about volleyball serves. As players, we strive to get the "perfect serve" which in physics terms means getting the ball to travel a certain amount of meters in the shortest amount of time. This mean the velocity needs to be as fast as it can while keeping the arc you would see in a d/t graph really low. (just high enough so it goes right above the net). This makes me wonder whether figuring out the right velocity and angle of elevation of the serve using physics formulae would actually help in order to make your serve as precise and accurate as possible.

Summary of Quarter 1

These past three units have really been centered on motion. We are constantly moving every second of the day - whether we are running, driving, or just breathing. This first week and a half of physics has helped me to put that constant motion into perspective to see how it really applies to us in our everyday lives. In unit 1, we learned about the units we use when referring to motion - acceleration, velocity, time, and distance. We put those newly learned units to use as we learned Kinematics in unit 2. We learned about how distance or velocity looks like on graphs. In this unit, many things we previously assumed had been challenged through our labs and activities. We learned things such as how we don’t feel motion when we are moving at constant speeds, or how the velocity of fast objects such as planes is 0 because the speed is constant. In unit 3, we learned about the effects of gravity on the motion we had been studying. We learnt through labs that everything is always accelerating downward and that gravity will pull down on objects with the same force no matter what its mass. In these three short units, I learned a lot about motion and it helps me to see movement around me with a new perspective.

Unit 3 cont.

Today, we learned about Acceleration, and was introduced to the Galileo experiment. Although I had heard about his findings, it was still hard to understand why when we saw the demonstration. Mr. B dropped a tennis ball and volleyball from the same position in the air. To our amazement (no matter how many trials we conducted), the two balls, which are clearly different in weight, hit the floor simultaneously. This reminded me of the free fall ride at knots berry farms. Regardless of how many people in the carts, (how heavy the cart is) the cart still falls at the same rate. This shows that gravity affects all objects regardless of mass. Before this lesson I would have just assumed that carts with more people and therefore more weight would drop at a faster rate on the ride. Yet Galileo's findings continuously proves to us that even though no one was on the ride, the cart would still drop at the same rate as a cart full of people, because gravity affects all objects equally.

Unit 3

In Unit 3, Uniform Acceleration, we learned a lot about acceleration of objects and how the pull of gravity on our planet affects that. In class today, Mr. B did a demonstration of an object being thrown up in the air. How after you throw an object in the air, the force of gravity starts to act upon the object and as it reaches its maximum height, the object slows to a stop. After that split second of a standstill, the object starts to accelerate downwards, reacting to gravity. This made me think of the famous rollercoaster in Japan, the Dodonpa. I rode it dozens of times, yet I never thought about how or why it worked. For a while you are carried up to the top of the rollercoaster, your potential energy rising with every meter you climb. Once you are at the top, you are the standstill I mentioned above. For that second, you are not moving at all, then gravity starts to pull the car down. As gravity starts to work its magic, you are accelerated downward, plummeting toward the ground as you surrender everything to the immeasurable power of gravity.  

Unit 2 cont.

In Physics today, we continued our learning of Kinematics. We experimented with v/t graphs and d/t graphs through our Graph Matching Lab. This made me think about the oceans our island is surrounded with. The waves move at a constant rate, yet they are constantly moving in different directions. Therefore the d/t graphs for waves would look like curved, constant intervals. It would go up and down at a constant rate, like a curved heartbeat. The v/t graph would jump from (for example) 2 m/s to -2 m/s periodically. Many d/t and v/t graphs look different though they may be graphing the same motion. But thinking about it further, I realized that waves are one of the few times when the d/t and v/t graphs look really similar.

Unit 2

Learning about Kinematics in Unit 2 taught me that our body only feels acceleration. When our bodies are moving at a constant velocity regardless of what velocity that may be, we will not feel it. This triggered me to think about bungee jumping. I went bungee jumping when I was little and I loved the feeling of being suspended in air. Yet now I realize that the cool aspect of bungee jumping was not the actual jumping; It was how you are being thrown hundreds of feet into the air, but you don’t feel it at all because you are moving at a constant rate. I realize now that you don’t actually feel it when you are in the air, only when you are at maximum and minimum height.

Unit 1

In this unit, we reviewed a lot about scientific notation, sizes, and units of measurements. Learning about all the different units of size, I finally connected prefixes such as "giga", "mega", or "kilo" to memory - a concept we constantly refer to. When talking about our iPhones, memory sticks, or file sizes we often throw around phrases such as "my iPhone is only 8gigs" or "this stick is 2gigs, will my pictures fit?", etc. I was using phrases and terms such as these even though I didn’t really know what it meant. This unit helped me to connect the two concepts that when we say "gig" we mean 10⁹ bytes of memory. I thought this was really interesting because we think that 8 gigs is not that much memory, as many people need the 16 gig iPhone to store all of their music, photos, texts, apps, etc. but it actually is 8,000,000,000 bytes of memory. Through this unit, I was able to put these terms into perspective to see how big a gigabyte (10,000,000,000 bytes) or a megabyte (10,000,000 bytes) really is.

Letter of Introduction

My name is Remi Yamashiro and I was born and raised in Tokyo. Music is a huge part of my life, as I love to sing, listen to music, and play piano and taiko. I also love to paddle, and I am currently paddling for Hui Nalu for the summer regatta season. I moved here as a freshman and have learned to love Hawaii and the people in it. Although science has never been my strong suit, I have enjoyed my science classes here at Punahou. I took biology as a freshman, and chemistry honors as a sophomore. After the summer course of Physics, I am taking AP Environmental Science during my Junior year. I took Geometry during my sophomore year for math, and through the summer physics course I hope to finally be able to see the relationship between classroom science and real-life science. My picture that represents who I am is a picture of Jerry for many reasons. Not only was Tom and Jerry one of my favorite cartoons growing up, I was born in the year of the mouse and I believe that says a lot about me. Jerry loves music, as do I, and the way Jerry playfully interacts with Tom symbolizes my playful relationship with some of my good friends.