What I Learned This Semester

This semester I honestly learned a lot more than I thought I would’ve. I wasn’t too nervous about taking physics because I’ve always liked science classes. I learned that my teacher teaches the concepts of each unit and it’s up to us as students to apply them to problems as well as everyday life. I really liked the momentum and energy unit. Because both have law of conservations, it made the whole concept really easy to understand. I’m a bit upset at myself because I could’ve done much better first quarter with the kinematics units. Now that I look at the problems and equations I feel really dumb for not being able to understand them. The second quarter was much better for me and I feel like I better applied/prepared myself for the tests and quizzes. Altogether I really look forward going to physics class. The learning environment is fun when it needs to be and I still learn a lot, which is perfect. I am really happy I got the teacher that I did because I feel like all my friends with the other physics teachers are suffering big time when I feel excited about physics. This semester I learned a lot about.

The Law of Conservation of Momentum

Momentum is inertia in motion. The Law of Conservation of Momentum is momentum cannot be neither created nor destroyed. This means that the momentum put into something is equal to the momentum that will come out of it. By the two being equal to each other, it means that momentum is always conserved. Even when other external forces act upon an object, there is always an opposite force that makes the momentum of the object equal. Both force and momentum are vector quantities and that the momentum conservation principles apply separately to each coordinate direction. Impulse is the change in momentum.

What is a force?

A force is defined as a push or pull. It is also defined as something that accelerates objects. If a single force acts on an object, its acceleration is found to be in the same direction as the force. If more than one force acts on an object, its acceleration is the direction of the vector sum of the forces. A normal force is perpendicular to the surface and is only acting upon an object when the object is on top of a surface, not in mid air or anything like that. The normal force occurs because when an object is upon a surface it causes a small force upon the surface of the countertop, just as the countertop does the same to the bottom of the object.

Potential and Kinetic Energy

Energy, in a physics sense, is defined as the ability to work. Work is the force placed on an object multiplied by its displacement or distance. Anytime the energy of something changes, it’s called work. There are two types of energy also. The first type is potential energy. Potential energy is energy stored in a system due to its position. My Hello Kitty toy shows potential energy because I was cranking the lever, which caused stored energy, or potential energy inside of the toy. The other type of energy is kinetic energy. Kinetic energy is energy in motion or something that is moving. Hello Kitty shows kinetic energy in the next picture because she is in the middle of moving sideward’s after I cranked the lever.

Egg Drop

This week my blog post will be about my egg drop project. My partner was Rachelle and in preparation for the egg drop project I spent a whole day after school at her house. We walked around in Target for two hours after brainstorming some ideas. We decided to use bubble wrap as our bag or container because that absorbs a lot of shock. Then on the inside we decided to use Timothy hay because we noticed that if you packed it in tightly, the egg on the inside wouldn't move. We also noticed that by stuffing the bubble wrap with something, it'd made the shape of the bubble wrap rounder which would've helped to absorb more of the shock. Unfortunately after all our hard work, the egg cracked anyway. It most likely cracked because it bounced, which was what we were trying to avoid entirely. I realized we could've done much more simpler things or even used cotton balls to stuff the bubble wrap instead of hay.

Collisions

 

I learned that there are two types of collisions when it comes to momentum. One is elastic collision and the other is inelastic collision. An elastic collision is one that is bouncy; the initial kinetic energy is conserved, meaning that the momentum transferred in from one object is equal to the transferred momentum out the other object. An inelastic collision is one that is sticky; the initial kinetic energy is not conserved, meaning that the momentum transferred in from one object is not transferred out the other. In inelastic collisions, the objects usually come to a stop and in elastic collisions the object that the initial momentum acted upon receives whatever the initial momentum transferred to it. A good example of this would be car collisions. Sometimes in car crashes the cars are squished together (inelastic) and sometimes one car is propelled from the other cars momentum (elastic).

 

Momentum

My definition of momentum is the amount of something it takes to make something move. I think it relates to acceleration, mass, magnitude and most definitely inertia. When I think of the word momentum I think of an object having to swing back and forth to a certain height in order to clear the distance of something. The Webster’s Dictionary definition is: the quantity of motion of a moving body, measured by a product of its mass and velocity. I was kind of close to the Webster’s Dictionary definition. Momentum has to do with the muchness of the moving of an object.

Newton's Second Law of Motion

Newton's Second of Law of Motion is that acceleration of an object is directly proportional to the net force on an object. But, the acceleration is inversely proportional to the mass of an object. This is a picture of my two brothers throwing two of the same size ball. I know that the baseball goes faster because the mass of the object is greater than that of the tennis ball. Newton’s Second Law also tells me that acceleration is inversely related to the mass of the object meaning that the more mass something has, the slower the acceleration would be. Also the less mass something has, the faster it will accelerate.

First Law of Motion

This is a picture of my friend Brachelle blocking a ball with another ball when she was playing dodge ball at our Ring Social this past Friday. This picture shows Isaac Newton’s First Law of Motion, which is objects in motion will tend to stay in motion unless acted upon by an outside, unbalanced force. The green ball in the picture coming towards Brachelle remained in motion until she hit it away with the purple ball which acted as the outside, unbalanced force that stopped the green ball from remaining in motion. Newton’s First Law of Motion also states that objects at rest will tend to stay at rest unless acted upon by an outside, unbalanced force.

Extra Credit

Cars

A vector is something that shows direction and magnitude. An example of a vector is a car. A car goes in a multitude of directions and can travel at many different speeds. I had a behind the wheel with my driving instructor and I noticed that cars relative to me and are going the same speed appear to be going no where from me, they look it looks like we are moving as one. Also, I noticed that when cars are opposite from the median relative to me, they appear to be passing really fast even though they are probably going the same speed. They appear to be moving really fast because they are going in the opposite direction.

What is A Vector?

A vector is a quantity that is specified by both a magnitude and a direction. Magnitude is muchness and direction is in which way something is going. An example of vector would be arrow. An arrow points in directions and tells you how far you can go. You usually find arrows on signs, directing people towards places. Along with the sign, you usually find how far you need to go in the direction that you intend on going. The half arrow above the letter A in my picture is symbolizes that the arrow above is a vector and it’s called boldface.

Running For Days.

My friend Ilihia is such a committed athlete. She always finds time to run either during school or afterwards. Her goal is to run at least three miles per day. However, Ili tells me that throughout the time she runs, she doesn't run at a consistent speed. Sometimes she slows down or speeds up, depending on her mood. In other words this relates to Physics because, Ili changes her acceleration and speed over the period of time she runs. She may run 3 feet per 5 seconds at one point in time and after she gets tired she might run 3 feet per 10 seconds. So if you were to find her average, it wouldn't be accurate because of the fact that she doesn't run at a consistent speed.

More Kinematics

This is a picture of my friends and I at a gymnastics place jumping on a trampoline. This shows Kinematics because each one of us are jumping with different velocities and speeds. Some of us were jumping higher than others, which kept us up in the air for a longer period of time. Some of us jumped quicker than each other, which means we jumped at different velocities. I can calculate how high I jump using the formula d = vt. For example if I jumped up at 1 meter per second squared for 1.5 seconds I would have jumped up 1.5 meters.

Treadmill

Kinematics is the study of how things move. On a treadmill, you have the ability to exercise and stay in the same place at the same time. When you exercise on a treadmill you neither move forward, or backward. The belt underneath you is what moves. You neither gain nor lose distance.  The displacement for exercising on a treadmill will always be 0, because you don’t change position, you can only change the speed or distance. You can also run or jog at constant rates because you control your speed through the belt on the treadmill and you have to keep up with the belt.

Kinematics

 Kinematics is the study of motion. These pictures of my brother relates to Kinematics because he is creating motion when he throws the baseball. In baseball, a pitcher throws a ball to the catcher and the batter of the opposing team has to hit it. The velocity of the pitch (or how fast the ball goes) depends on how hard the pitcher throws it. With physics you can calculate how fast the ball is going. The formula for average velocity is displacement*elapsed time. So if my brother was pitching from a mound that was 60.5 feet away from home plate and it took the ball 3.8 seconds to get there, I can use the formula average speed = displacement*elapsed time to figure out that he throws around 70 miles per hour.

Tape Measure

This is a picture of a tape measure. This is an example of the unit we did because it has to do with measurement. A tape measure is used to measure things. Specifically, this one is used more so for construction, there is another type used for tailoring. It is common that there are metric units on one side and imperial or British units on the other. This applies to physics because people use it to measure the length or width of things so they are able to resize different things or see if they need to make it longer. In physics, they use the metric system to measure things. For instance, we used a meter stick to measure the string part of the pendulum for our lab and a tape measure has the same units you can measure things with.