Science Methods II Week 3 Blog Post

 1. The big questions discussed in lab, and a description of what you did

        -     What affects a rider's speed down a slide?

        -    During lab this week we picked a variable to test to see how it would affect a rider's speed down a slide. The variable we chose to test was the weight of a rider. In this experiment the two independent variables were the height and length of the slide. The height was 86cm, and the length was 252cm. The dependent variable was the weight of the three riders, which was represented by cars. To increase the weight of each car, we added washers on top. The three weights were 54g, 72.4g, and 94.7g. We put each car down the slide three times and took their average speed. From the lowest weight to the highest weight, their average speeds were 1.28s, 1.43s, and 1.51s. In the end we concluded that as the weight increases the longer it takes for the rider to reach the bottom, however, the weight change and the speed change were not too significant, so we also concluded that the weight does not have a huge affect on the speed of a rider down a slide. 

 2. A description of what you learned in Thursday's lecture

        -     This week in lecture we went over the different variables that we tested in lab (height, steepness, surface/clothing, & rider weight). For each of them we discussed why they matter and what we found out when we tested them. For example, for the height of a slide we found out that the higher the slide is, the faster the riders speed will be. We discussed that the height of a slide is significant because acceleration occurs as you are going down a slide, and if the slide is at a higher height, there is more time for the rider to accelerate and go faster. We also learned about both force and friction. We learned the force is a push or pull that is needed in order for an object to speed up, slow down, or change direction. Lastly, we learned that friction is the opposition force when someone or something slides across a surface.

 3. Answer questions about the weekly textbook reading:

        -     What did you learn?

            -     Something I learned from the textbook reading is the difference between kinetic friction and static friction. Kinetic friction is occurring when someone or something is in movement, for example, someone going down a slide. On the other hand, static friction is what is happening when something is not moving or is staying still. This may be a car being parked on a slope, not moving because of the opposing force of friction. 

        -     What was most helpful?

            -     What I found most helpful in this reading was the different simulations and videos included. The phet simulations were helpful in understanding the meaning of force and how objects move when there is an imbalance in forces. Getting to move the people ourselves and adjust the settings allowed us to do our own testing rather than watch someone else's testing, which in the end allowed us to obtain a better understanding of the concept. 

        -     What do you need more information on?

            -     Something I would like more information on is the idea of charged particles and objects either attracting or repelling each other. I understand that opposite charges attract each other, while the same charges repel each other, however, I would like to have some more information on why this happens and if there are any exceptions to it.

        -     What questions/concerns/comments do you have?

            -     A comment I have is that I like how it explained each of Newton's Laws in detail. In high school I mainly remember hearing about the first law, so this was good to have a refresher on that as well as gain more information on the other laws.