1. EARTH AS A SPHERE 9.4 Understand and use the concept of distance on the surface of the earth to solve problems

2. Learning Outcomes Find the shortest distance between two points on the surface of the earth.

3. A B (37 o N, 54 o W) (37 o N, 126 o E)

4. A B

5. A B (37 o N, 54 o W) (37 o N, 126 o E) 180 o Answer

6. The distance between A and B = 180 o x 60 = 10 800 nautical mile

7. A B

8. A B 37 o O AOB Next 0o0o

9. AOB = 180 – (37 o x 2) = 106 o Back

10. The distance between A and B = 106 o x 60 = 6 360 nautical mile

11. Conclusion The shortest distance from one point to another on the surface of the earth is along a great circle.