Eratostenes method

G.A.M.E on March

Calculating The Circumference Of The Earth Using The Eratosthenes Method

List Of Needs For The Event

 1 meter long stick

 Ruler

 Miter

 Pen

 Paper

The Steps Of The Activity

 1. step: Our stick should stand VERTICALLY on a flat surface at an angle of 90 ° with the ground.

You can use a miter to check the 90 degree angle and make sure the floor is flat.

The Steps Of The Activity

 2. step: The Sun is expected to reach its highest position during the day at the current coordinates after the setup is established.

Internet time should be used as time, measurement errors should not be made.

You can use the link below to find the right time in the city you live in.

https://www.suncalc.org/#/40.1789,-3.5156,3/2021.02.22/22:48/ 1/3

The Steps Of The Activity

 3. step: Measure the length of the shadow of the rod when the sun is in its highest position.

For example, we measure the length of the shadow 76.2 cm.

You can get help from a calculator or the internet to find the angle teta and use the concept of ‘arctan’.

θ = 37,30740066

The Steps Of The Activity

 4. step: The distance from where we live to the equator must be found. Because when Eratosthenes was doing this experiment, in one of the two cities the Sun was right on the top and the rod had no shadow. On the other hand, in our activity, we accepted the second city as if it was on the equator.

 You can learn the distance of the city we live in to the equator with the following link.

https://www.google.com.tr/intl/tr/earth/

For example, we found the distance between Samsun and the equator as 4152,52  km.

The Steps Of The Activity

 5. step:The central angle around the earth is 360 degrees. If the central angle seeing the distance ΔS is θ degree, the circumference can be calculated as follows.

The Steps Of The Activity

 6. step: After all measurements are made, the shape of the world is drawn on the paper and the distance and angle found are placed on the model. The circumference of the world is calculated by making the necessary calculations. Finally the paper is photographed.

 7. step: During the event, you should take many pictures in a mask. Then you have to create a booklet in the storyjumper program and upload the twinspace pages.

https://www.storyjumper.com/