Graphing Kinematics

During class on Thursday, everyone had to examine graphs and find how they apply to the relationships involved in kinematics. Although these two graphs appear different, they both demonstrate what happens when a ball is thrown in the air and then caught at the original position. The top graph measures the relationship between time and velocity. The line with the negative slope represents the ball's movement in the air. As the ball reaches the top of its path, its velocity slows down to 0 meters per second, which is why the line crosses the axis of time in the graph. Also, the velocity of the ball's downward path is negative because the ball changes direction but the speed going up is the same as the one going down. The bottom graph represents time's relationship with acceleration. Interestingly, the acceleration of the ball is constant while it is in the air. Although the velocity of an object may increase or decrease, acceleration will be the same because gravity will always force the object to accelerate a certain way. Only an outside influence, such as catching the object in one's hands, will affect the acceleration.

Running in Circles

This weekend, I started to train for my event for physical education. My main goal is to finish in any place except for last place. Each day, I jogged for ten minutes around my neighborhood, which consists of a set of apartments assembled in a loop. Jogging is a definite example of kinematics. When time increased, my distance increased. Since the loop is not on a flat surface, my velocity decreased whenever I had to travel up the parts that were steep. Since gravity pulls objects downward, jogging down the loop led to an increase of velocity. However, my final displacement was 0 units of length because I ended up at my origin, which in this case was my home.

Labor Day Weekend

This year, my birthday occurred last week Wednesday. As a result, Labor Day Weekend was basically a sequel to the festivities. During that Sunday, I spent more than two hours at Waikiki Beach. I am aware that Waikiki is definitely tourist central but the beach was relatively mellow that day. Of course, if it was spring break right now, I would not be saying the same thing. While I was swimming in the ocean, my movements involved the principles of kinematics. Whenever I changed directions, my acceleration and velocity also changed. At times, my acceleration was negative because I would go past my original position. As time passed, my distance would increase as I swam. However, I often spent minutes at a time in a particular part of the ocean, which means that I did not move constantly. Although the force of the waves did affect my velocity, the general factors of kinematics were still relevant.

Kinematics

The subject for Unit 2 of Physics is kinematics, which is the study of motion. Today, I took this picture of a screen on an exercise bike. The distinct blurriness of the image is due to changing numbers. The top number is the time measured in seconds. In this instant, I was on the bike for 26 seconds. The number on the bottom left-hand corner is the distance in miles. The distance at that moment was 0.04 or two-fifths of a mile. This bike is an example of how distance and displacement are different from each other. Since this is a stationary bike, my displacement is zero because I never travel away from my position. However, my speed on the bike combined with how long I rode it calculates to a certain distance, which does not include direction. Located next to the distance is the speed. In this case, my rate was 4.8 miles per hour. However, like cars, this bike can only measure one's instantaneous speed. Once I move faster or slower, the number changes to represent that particular speed. As a matter of fact, my speed reduced to 4.6 miles per hour after only 2 seconds. The factors of distance, time, and rate are all connected to kinematics. Changing one factor can affect others.