Begin the pre-lab by viewing what to expect in the pre-lab section, directly from
Dr. Harry Shipman.

This pre-lab for The Shadows of Light contains links to several other pages introducing you to the investigative problem associated with this lab.  Furthermore, the material which you should look at on the World Wide Web before you get to lab, as well as your pre-lab assignment, is also included. Your instructor will tell you whether the pre-lab assignment should be done as individuals or as a group.

The investigative problem is a real-world quandary that focuses your learning during the lab.  Dr. Harry Shipman has been an expert witness on problems like this in an actual lawsuit.

Flashlights and Flagpoles

You will use a flashlight and a tiny model of a vertical stick to explore the relationship between the length of a shadow cast by an object and the position of the sun in the sky. These shadows could be cast by a vertical stick or flagpole, a building, a fence, or anything. In the real world you can't move the sun around, but in laboratory you can move a flashlight around and observe the length and position of the shadow.  To illustrate this concept, visit the two links below. 

• A picture of a flashlight casting a short shadow.
• A picture of a flashlight casting a long shadow.

Flagpoles and Rotating Globes

During the in-class portion of this lab you shall utilize several globes, each of which has tiny pins on it placed in strategic positions located in reference to this problem (Newark, Delaware, and Cancun, Mexico) as well in Juneau, Alaska. You can shine a light on these globes so that the tiny pins cast a shadow, and thus you can follow what shadows look like from various locations at different times of the year. Take a look at the link below to see a video of one of these tiny pins casting a shadow. 

• View video of globe with a pin casting a long shadow

Why Are We Doing This in The Course? 

Some of my astronomer friends have argued that since the seasons are taught in the 5th grade, we should not be doing this in college. However, there is evidence that many smart people were taught the seasons poorly and did not learn why it's warm in summer and cold in winter in the continental United States, as in many other parts of the world. If we are to break the chain of failing to understand this important topic, we must teach it in college, at least until the next generation, which is beginning to be experience this topic in a somewhat more constructive way than I was, becomes our students. 

Pre-lab Assignment 

Explore the "PBL Center" and "Prelab" sections of the "Shadows of Light" website so that you understand what is going on in lab and why you are doing this.

Find at least one website which describes an activity for K-8 students that has something to do with the seasons. You may, if you wish, use the links available in the Web Sites menu on the Shadows of Light frontpage.  Use these sites to aid your investigation of the problem and answer the two questions below.

Read and think about the problem and the materials which are described above. Answer the following questions:

• What does measuring the length of a shadow tell you about the position of the sun in the sky?

• In one paragraph, compare this seasons activity with the one which you found in searching the world wide web. Be sure to mention the URL of your website in your response.

Full credit will be given for a serious attempt to analytically answer this question.

Your instructor will tell you how this pre-lab assignment is to be submitted.