Equivalent Vectors

In Physics, we use vectors as measurements.  A vector quantity has magnitude (size & unit) and direction (N, E, S, W).  Another way of remembering vectors is "how much and which way".  Velocity is an example of a vector because it tells how fast an object is going and in which direction.  In the picture above, there is two columns; one of an example of an equivalent vectors, and the other is an example of a non-equivalent vectors.  The reason the left column arrows are equivalent to each other is because they both are pointing North and are relatively the same size.  In the right column, we can tell that these two arrows are not equivalent vectors because first of all, they are pointing in two different directions, and second of all, the green arrow is shorter than the pink arrow.  A vector is only equivalent to another vector when both its' magnitude and direction are the same.

What Goes Up, Must Come Down

This week, we did the Ball Toss Lab.  When Coach Chris showed us an example of what we were doing in the lab, he took a volleyball and threw it up 2 meters and then caught it at the same level he threw it from.  This reminded me of when my friends and I were trying to capture a picture of us jumping together. Coach Chris taught us that when an object is thrown in the air, its velocity goes slow, fast, stop, slow, fast.  This weekend I was just looking over my pictures and I remembered when we were all jumping in the air! It made me think that when we were jumping that we started off slow, then sped up as we got to the top, and then stopped in the air, and as we came down it went slow, and then fast as we hit the floor. This Ball Toss Lab helped me realize that whenever something goes up, it must come down, but when it is in the air, it has different velocities.

Position vs. Time

This week in Physics, we did a lab that once again dealt with kinematics.  In the lab, we studied how motion worked in using a Motion Detector.  From using the Motion Detector, I learned that when an object stays in the same place for a certain amount of time, then the graph shows a line with a slope of 0.  When an object moves in a forward direction, the graph shows a decreasing slope.  When an object moves in a backwards direction, the graph shows an increasing slope.  So, in other words, I learned that the direction in which an object is moving and the time it takes to move that certain distance affects the direction of the graph.

Direct Relationships

Last week, we did the Physics Olympics Lab.  In the lab, we did 3 different activities: bunny hop, posture practice, and a gentle jog.  In all 3 events, a person in our group was timed to see how fast they could go for a distance of 50 m.  In the lab, I learned that position and time have a direct relationship because after all our data was collected, the graph was a straight line.  That means as time went on, so did the distance.  Kinematics relates to the real world because it is the study of motion and we use motion in our everyday lives.  A real world example of a direct relationship is the speed of a car and its distance.  As the speed of a car increases, so does the distance (and vice versa).  Learning about direct relationships has helped me to more about kinematics and it gave me better understanding of how things work in motion.