Real and Virtual Images

Learning Goal 2.2: I can reason and make quantitative predictions about real and virtual images formed by lenses and mirrors.

This week, we talked about convex and concave mirrors, along with real and virtual images. While I didn't fully understand the difference between real and virtual images, there were still some pretty cool things that I observed, like how a real image flips upside down beyond the focal point. We also did an activity involving a candle flame, lens, and paper board all placed on a meter stick. The flame of the candle projected an image of the flame onto the board. It was interesting to see how the clarity and size of the image changed as the lens was moved further and closer to the lens. The lens was later altered so that the flame was projected through a pinhole.

Refraction Angles

Learning Goal 2.1- I can describe the phenomena of reflection, refraction, and dispersion of light with the ray model of optics.

This week, we began a new unit: ray optics. Our first activity was the gold rush worksheet, where we tried to find the fastest route between 2 points. My group found that in this case, a straight line would not be the fastest way between the points because of the 2 different terrains. After finding the fastest time, we then applied the same concept with a real model of an acrylic and light ray. I've struggled a bit with understanding Snell's Law, but I think Friday's worksheet somewhat helped. 

Unit 1 Project

Learning Goal 1.2- I understand where I am situated (physically) in the universe.
Learning Goal 1.3- I can describe the historical context and impetus for the development of natural philosophy.

For my project, I chose to write a research paper covering focusing on learning goals 1.2 and 1.3. The paper covers the historical background for scientific discoveries and achievements. I hope to compare different philosophers' viewpoints and further enhancements on similar discoveries, and also talk about how those discoveries are integrated into what we learn today. One topic I talk about is the discovery of lunar phases, which is often credited to Galileo; picture source is https://en.m.wikipedia.org/wiki/Sidereus_Nuncius#/media/File:Galileo's_sketches_of_the_moon.png.

                                                  

Earth's Circumference + Phases of the Moon

Leaning Goal 1.2- I understand where I am situated (physically) in the universe.

This past week, we learned about the different phases of the moon and how to measure the circumference of the earth. Beginning with the moon, I didn't find it too difficult to remember the stages: new moon, waxing crescent, 1st quarter, waxing gibbous, full moon, waning gibbous, 3rd quarter, and waning crescent. The only difficulty I had was differentiating waxing and waning. Later in the week, we measured the circumference of the earth using Nasif's model, which helped show the work of Eratosthenes regarding the curvature of the earth. We began by measuring the height and width of the sticks on the model, and using those numbers to determine the necessary angle (14 degrees). We then measured the distance between Alexandria and Syene on the model (30 cm) and set up a proportion to determine the earth's circumference based on the model. Then, we inserted the actual distance (843.6 km) in place of the 30 cm to determine the actual circumference of the earth. Our answer of 22, 000 km was about half off the actual circumference; this was because our angle of 14 degrees was incorrect due to inaccurate measurements of the height and width of the sticks. Similarly to last week, I noted the importance of accurate measurements.