SAMPLE: Surveying

Title: Now I Know Where I Am!

Background: Wanting to know where we are and where other people are is natural. But, until recent times, accurate information about distances and positions was sometimes hard or impossible to come by. Early surveyors would shake their heads in disbelief at the ease with which GPS pinpoints us on the globe.

Questions:

1. Make a simple sketch of the globe showing the orientation of latitudes and longitudes.

2. a) Please go to: http://www.thegreatarc.net/home.htm What was measured during the huge surveying project called the Great Arc?

b ) Look down the page and click on <trigonometric survey>. Please print the image of the Great Arc showing its enormous number of trigonometric measurements.

3. Close the image of the Great Arc and look again at the home page. What instrument was used to collect the data from which the Great Arc was created? Please print the image of the theodolite on the home page.

4. Name the two main figures in this endeavor.

5. In the end, the survey line was how long?

6. The difficulty of this 50 year long project can be compared to what recent scientific accomplishment?

7. Click on <George Everest>. How did he ensure survey observers had a clear view between reference locations?

8. Read down and describe how men and materials moved about.

9. An elephant wanders 1.3 km along 70⁰ before turning and moving 3 km along 280⁰. From that point, find the direct route (distance and direction) back to the start.

10. a) A boat crew rowing across a lake at 0.9 m/s encounters a 0.15 m/s crosscurrent. If the crew makes no corrections, find their new direction and speed.

b) What corrections to direction and speed would the crew need to make in order to say on their intended course and speed.

c) How long would it take the crew to row across a 15 km wide lake?