Help with science homework - Experiment to prove the earth is round!?

Question

So my science teacher gave us the assignment to "prove that the earth is round." He told us specifically that it had to be something that could be an "experiment" (such as traveling around the world) and that we have an endless amount of money to conduct this experiment. my science teacher is trying to prove that the earth is flat

we've already gone through "travel around the world" and "take a photo from outer space" in class...

ANY IDEAS! please help!

Answer 1

digging to china!

Answer 2

Stand on the beach and look out as a ship/boat comes over the horizon.

Since the earth is round, you will first see the top of the boat, then more of it, then the whole thing. If the earth were flat then the whole thing would be visible all at once.

It proves the earth is round and it's free to do! :D

Answer 3

hmmm stare at a sky scraper up close.. and move farther away from it and watch as it gets shorter and shorter... hope that helps..

Answer 4

As well as the other ideas given, you could try the "experiment" Newton used to explain gravity.  Place a cannon on top of a tall mountain and fire a cannonball horizontally with sufficient velocity and it will orbit the Earth and hit you on the back of the head !

You could measure the latitude by sighting Polaris, the North Star, with a sextant and find that the angle varies from 0° at the Equator, to 90° at the North Pole, something that could only happen if you were standing on a sphere.  Also, 4 x 90° is 360° or a full circle, so if these measurements were repeated a significant distance apart, you would end up with a series of interlocking circles, or what we call a sphere.

Find a canal or similar stretch of water running in an uninterrupted straight line for at least six miles, like the one used in the famous Bedford Level Experiment during the 19th and early 20th centuries, then place a set of three poles fixed at equal height above the water level along this length.  Assuming the water is level, the middle pole will be almost three feet higher than the poles at each end when viewed carefully through a theodolite, showing the curvature of the Earth.

Hope this helps.

Answer 5

Watch an eclipse of the moon. Whan the earth's shadow falls on the moon, it's always curved. It won't cost you a penny to watch it, either.

Edit: Here is a good photo montage showing what I mean: http://www.perseus.gr/Astro-Eclipses-200...

Answer 6

Simply watch a ship as it enters the horizon - first you'll see the top of the ship, then the middle part and finally the entire ship.

This could only happen if the ship were coming over a curved surface.

Answer 7

Climb a tall building (or mountain for that matter) and look in every direction. You will notice that no matter in what direction you look, you can see further, the higher up you are. This shows that in every direction the Earth's surface falls away from you.

Repeat this simple experiment at as many places as you like. Except where vision is blocked, you will see it is true in every place. the only shape for Earth that will cause this is that of a sphere.

(You can do the reverse on the surface of the ocean, observing that it applies to tall buildings on land or the masts of other ships. The further you are away from them, the less of them you can see until when you are far enough away, they are below the horizon...