Elsa Petersen's Science Methods II Blog

Lab:  Earth viewer Activity:  Earth and Moon formed ~4500 Mya The oldest minerals show evidence of liquid water on Earth (~4400 Mya) About 2.4 billion years ago, oxygen began to persist in the atmosphere. Before then, life did not necessitate oxygen.  Snowball earth -- earth was covered in ice (2200-2000 Mya)  Cambrian explosion (540 Mya) -- diversification of life First land plants: (470 Mya)  First land vertebrates (375 Mya)  Permian-Triassic Extinction (~251 Mya) referred to as "The Great Dying" or the largest extinction event in history Genus Homo (2 Mya)  Homosapiens appeared much later -- 0.2 Mya With young students, it is helpful to use a timeline to illustrate the concepts of earth's conception and beyond. With the students, it could be easiest to create a timeline that details the last billion years to be more specific with a smaller span of time. Pressbook:  - The first life on Earth was simple, prokaryotic bacteria. - At least three tim...

 Lab:  Today we discussed the planets in our solar system, creating a model of the four planets closest to the sun. Our task was to create a proportional model, discovering how small the planets are compared to the sun and how vast our galaxy is. We decided to make our model 60 meters long, with our sun at 350mm in diameter. At first, we made our sun way too small, meaning our planets were a fraction of a millimeter in diameter, which did not work for this particular model. With that information, we lengthened the distance of our model, and made the diameter of the sun much larger so that we could properly create our model.  Sun: 0m                                                                 Mercury: 14.5m                    ...

 Lab:  In lab today, we explored the movement and phenomena relating to the sun, moon, and earth. We used globes and other manipulatives to represent each of these planets. After exploring the phenomenon, we discussed many big concepts of this unit, like the elliptical shape of the earth's orbit, the equinox/solstice, and some of the historical figures in this scientific area, Copernicus and Galileo. How do the phases of the moon occur?  I think that the moon's phases are caused by the sun lighting different parts of it based on its position in orbit around the earth. We can only see the lit portions of the moon here on Earth. What causes the seasons? The seasons are caused by the position of the earth relative to the sun, and when it is warmer during the summer, that portion of earth is tilted towards the sun. - After our exploration, we found that because of the earth's tilt, the portions of the earth that are facing the sun during its orbit experience warmer weather fo...

Lab:  This week in the lab, we conducted an experiment testing the differing surfaces that are present in playgrounds. Our goal was to keep an egg from cracking when dropped from 1m into a bowl filled with various materials common in playgrounds. Our first trial was not as successful because it had too much bounce. The egg would just bounce right out of the bowl and crack on the floor. We deduced that the rubber was causing the bouncing rather than absorbing the shock as we had previously predicted. To try and alleviate this problem, we then put woodchips on the bottom, a little bit of rubber, and then placed the straw around the sides and had a thin layer on the bottom of the bowl. That combination allowed our egg to drop safely, without bouncing from the bowl onto the floor. 

Lab:  This week in the lab, we explored swings and focused on the different factors that may impact the speed at which a swing travels when a person is using it. The variable that we decided to explore this phenomenon was the length of the chain on the swing. We had quite a few trials with four different lengths of rope on our swing. We dropped the swing at the same angle each time and measured the time it took to return to the same place after just one swing. After completing our investigation, we found that the length of the chain does impact the amount of time it takes for the swing to go back and forth.  Lecture:   This week in lecture, we looked at motion through an energy lens, investigating how energy impacts a pendulum as it swings back and forth. We did this through an online pendulum simulation, showing both the potential and kinetic energy that occurs when a pendulum swings. The most potential energy is at the peak height of the pendulum, while the most kinetic...

  Lab:   For lab this week, we were guided by the question, "What affects a rider's speed down a slide?". To explore this phenomenon, my group decided to explore the weight variable. To test this one, we decided to fill a film canister with various amounts of sand, testing how long in seconds it took to go down the entirety of the slide. As we continued with our investigation, we got slightly frustrated because the trials did not align with our hypothesis. We had assumed that as the weight increased, the speed of the rider would also increase, but the data we collected was not supporting that expectation. In the end we concluded that the weight of the rider does not impact their overall speed, because when the weight increased, the time stayed relatively the same.  Lecture:  This week we discussed the speed of a rider on a slide based on a few variables: height, steepness, surface/clothing, and the rider's weight. Throughout the lecture, we utilized the principl...

  1.        This week in lab, we discussed the question, "How do we make a race exciting between people who run at different speeds?". To answer this question, we broke into groups to try and figure out how much of a head start one runner would need to make a race exciting. My group did a series of trials, testing how much time it took for a few of our runners to travel 12 meters. That allowed us to find their speed in meters per second, giving us a good idea of how fast they could run if given a random distance to race.       After doing our work in small groups, we all came together and had a race against another group. Because the distance was randomly assigned, it was a bit difficult to accurately decipher what a fair and exciting race would entail. That being said, it was fun to collaborate with other groups who may have done their experiments differently than we did! 2.  In the lecture this week I learned more about how childr...