Lecture 7 unit 3 3(ii). Shape of the Earth

Shape of the Earth

1. Shape of the Earth Class: ADP II Semester QAU Islamabad Syed Abbas Hyder Shah Lecturer in Geography IMCG, Humak, Model Town Islamabad

2. Shape of the Earth Understanding Earth's Form and Structure

3. Introduction to Earth's Shape Earth is not a perfect sphere; it is a geoid or an oblate spheroid.

4. Geoid – The True Shape of Earth The geoid accounts for Earth's gravity variations and mean sea level.

5. Oblate Spheroid Concept Earth bulges at the equator due to rotation, with different polar and equatorial radii.

6. Historical Understanding of Earth's Shape Ancient debates and Eratosthenes' experiment estimating Earth's circumference.

7. Evidence Supporting the Round Earth Astronomical observations, ship horizon disappearance, sunrise and sunset variations.

8. Satellite & Space Exploration Evidence Satellite imagery, GPS technology, and space missions confirm Earth's round shape.

9. Airplane Routes & Gravity Distribution Flight paths curve due to Earth's shape, and gravity pulls toward the center.

10. Concept of a Geoid in Measurements Used in navigation, mapping, and geophysical studies for accurate elevation data.

11. Summary & Conclusion Earth is an oblate spheroid; modern technology provides overwhelming confirmation.