how did eratosthenes estimate the size of earth in 240 b.c.?

Answers

Answer 1

Answer:In 240 BC, how did Eratosthenes calculate the size of the earth? Using simple trigonometry, we compared whether daylight could reach water in water wells in two cities at different latitudes. The earth's system to set and a line that connects the globe to the sun are perpindicular on the spring equinox.

Explanation:

In 240 B.C., the Greek astronomer Eratosthenes made the first good measurement of the size of Earth. By noting the angles of shadows in two cities on the Summer Solstice, and by performing the right calculations using his knowledge of geometry and the distance between the cities, Eratosthenes was able to make a remarkably accurate calculation of the circumference of Earth. Let's take a closer look at how he did it!

Eratosthenes lived in the city of Alexandria, near the mouth of the Nile River by the Mediterranean coast, in northern Egypt. He knew that on a certain day each year, the Summer Solstice, in the town of Syene in southern Egypt, there was no shadow at the bottom of a well. He realized that this meant the Sun was directly overhead in Syene at noon on that day each year.

Eratosthenes knew that the Sun was never directly overhead, even on the Summer Solstice, in his home city of Alexandria, which is further north than Syene. He realized that he could determine how far away from directly overhead the Sun was in Alexandria by measuring the angle formed by a shadow from a vertical object. He measured the length of the shadow of a tall tower in Alexandria, and used simple geometry to calculate the angle between the shadow and the vertical tower. This angle turned out to be about 7.2 degrees.


Related Questions

What year was Taft brought into office?

Answers

Answer:

1908...

Explanation:

Taft was elected president in 1908, the chosen successor of Theodore Roosevelt, but was defeated for reelection by Woodrow Wilson in 1912 after Roosevelt split the Republican vote by running as a third-party candidate. In 1921, President Warren G.

Mark as Brainliest please...

Someone pls help me I will make you brainly

Answers

The answer above me is correct the marriage conjoined them

What are characteristics of culture?
Select all correct answers.
language
religion
o intelligence

Answers

Answer:

religion may be

Explanation:

Culture has five basic characteristics: It is learned, shared, based on symbols, integrated, and dynamic. All cultures share these basic features. Culture is learned. It is not biological; we do not inherit it. ... Despite the shared nature of culture, that doesn't mean that culture is homogenous (the same).

language and religion. we already know religion is a HUGE part of many cultures but language can be too!

95 POINTS PLEASE HELP!!
Compare how the first amendment was used in colonial times and how it can be used today. How are they the same? How are they different?

Answers

how the first amendment was used in colonial times and how it can be used today.

It protects our right to express our deepest beliefs in word and action. Yet most Americans can't name the five freedoms it guarantees – religion, speech, press, assembly and petition.

How are they the same? How are they different?

Both of these Bills of Rights are expressly designed to amend the constitution of each nation and act as a living document to spell out various legal matters, particularly rights and liberties.

hope it helps

Fill in the blanks: 1. The peasants and indigenous communities hated the exploitative system of​

Answers

Answer:

British

Explanation:

What are the two theories about the relationship between Emperor Honorius and the barbarians? Which theory did Procopius believe, and why?​

Answers

Theories claim that when Emperor Honorius left the palace when he saw that the barbarians were approaching and that he paid the barbarians to attack his kingdom. Procopius believed more in the theory that he abandoned the castle and fled.

We can arrive at this answer because:

Procopius claims that barbarian attacks were not a great concern for Emperor Honorius.That's because he believed his realm was too far away from where the attacks were taking place.However, when the barbarians began to approach, he began to fear a possible attack.There is a theory that when the barbarians got too close, he fled far away. Procopius believes that this theory is the truest and closest to reality.Another theory claims that he paid the barbarians to attack his kingdom, as this attack would fight rebellions from his subjects.

Procopius does not believe in this latest theory and there is not even evidence that it could be real.

More information:

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which was the worse year in human history.. 536 or 2020​

Answers

Answer:

536

Explanation:

Imagine waking up, to no sun in the sky at all, and no answers as to why. Darkness is all you see outside all the time, and you truly don't have any idea as to why, maybe its a punishment from god, maybe its a demon, or maybe its just natural? who knows? you sure don't.

Foods taken to the new world:

Answers

Answer:

wheat, rice, barley, oats, coffee, sugar cane, citrus fruits, melons

Explanation:

Food taking to the new world was wheat, coffee, rice, oats, barley, citrus fruits, sugar cane, melons.

Companies use __________ to know whether or not a region is growing enough to sustain new business.
A.
historical maps
B.
population trend information
C.
current news articles
D.
opinion poll results

Answers

The answer is B……z..,
B. Population trend information.

To which factor can the principles of Nicholas Steno be applied

Answers

Answer:

i cant give you an answer because there is not enough info to give an answer

Explanation:

the italian states played a crucial role in politics because of

Answers

Answer: there current riches

Explanation: I’m noT sure what time period your talking of but around when America was at its start Italian government had a lot more recourses and power then America since they’ve been a powerful country for a very long time. Hope this helps :) if it didn’t please tell me what time period your talking about and I’ll try my best to help you!

i need help to find out which one is the answer

Answers

were all brought to the Caribbean as indentured laborers

Why do historians and archaeologists believe that Harappa and Mohenjo-Daro had organized governments?

Answers

Answer:

A

Explanation

Was offered only to American Indians

who ruled Egypt while the Shang dynasty ruled China?

Answers

Answer:

The Shang tribe grew into power around 1600 BC. Legend has it that the Shang were united under the leadership of Cheng Tang. Cheng Tang defeated the evil King Jie of the Xia to begin the Shang Dynasty. The Shang ruled an area around the Yellow River Valley for around 500 years.

Explanation:

what does prohibition mean ?

Answers

Answer:

Prohibit sale & manufacture of alcohol

Explanation:

Answer:

Prohibit the sale & manufacture of alcohol

Explanation:

The first and second answers both mean to prohibit something or forbid something by the law but, prohibition could also mean "the prevention by law of the manufacture and sale of alcohol, especially in the US between 1920 and 1933."

Hope this helps

basahin nang malakas ang mga sawikaing nabuo mula sa larawan. Ibigay ang kahulugan ng bawat Isa. 1.taingang Kawali 2.pusong mamon 3. balat sibuyas 4.suntok sa buwan 5.dilang angel​

Answers

Answer:

1. Nagbibingibingihan

2. madaling magpatawad, mabait

3. tanong madaling masaktan, madamdamin

4. mahirap gawin

5. nagkakatotoo ang sinasabi

Napoleon kicked the?

Answers

Answer:

hornets nest?

Explanation:

what is the question is asking lol

why were britain and france rivals in the mid-1700s

Answers

Answer:

During the 1700s, Britain and France were two of the strongest powers in Europe. They competed for wealth and empire in different parts of the world. This rivalry caused bitter feelings between British and French colonists in North America. They did not want British colonists sharing in their profitable fur trade.

Explanation:

Please help math problem

Answers

Answer:

the value -1 evaluated on the function n + 5

so, the result is 4

How did Marcus Garvey MOST impact African Americans in the early 1900s?
A)
By desegregating schools and urban neighborhoods
B)
By urging blacks to accept low-paying jobs and social inequality
C)
By promoting black cultural pride and economic independence
D)
By supporting the use of violence to overthrow government and win
reforms

Answers

Marcus Garvey was a descent of Jamaican, a leader of the Pan-Africanism movement and founder of Universal Negro Improvement Association.

Marcus Garvey was a Black-American which sought to unify and connect the people of African descent worldwide.

He was very popular for organizing the U.S. first Black nationalist movement after the WWI where he advised the blacks to be proud of their identity.

Therefore, Option C is correct because he promoted black cultural pride and economic independence.

Learn more about Marcus Garvey here

brainly.com/question/4421138

why does the federal government have an interest in events

Answers

Answer:

Undoubtedly the biggest event in the growth of the federal government was the Civil War, which established its supremacy over the states. The Civil War brought much new power to the federal government, and laid the groundwork for the growth of interest groups.

Explanation:

What is the difference between Britain and British ?

Answers

Answer:

Britain is a country and British is the language or people of Britain, like United States and American

The land ordinance of 1785 was

Answers

Answer: Passed by the U.S. Congress under the Articles of Confederation. It laid out the process by which lands west of the Appalachian Mountains were to be surveyed and sold

Answer: The Land Ordinance of 1785 was passed by the U.S. Congress under the Articles of Confederation. It laid out the process by which lands west of the Appalachian Mountains were to be surveyed and sold. The method of creating townships and sections within townships was used for all U.S. land after 1785.

Explanation:

What did the Abolitionists do? worked for rights for African Americans fought for racial segregation they were black freedom fighters they fought for the continuation of slavery

Answers

The goal of the abolitionist movement was the immediate emancipation of all slaves and the end of racial discrimination and segregation. The Abolitionist fought for racial segregation and were black freedom fighters.

What was the Abolitionist movement?

An organised attempt was made to abolish slavery in the United States during the abolitionist movement. Female, male, former slaves, and those born free are battling against slavery in the abolitionist movement. By promoting equal rights and abolishing slavery, they challenged both their local communities and all Americans to change for the better.

As the name suggests, an abolitionist was someone who worked to end slavery in the 19th century. More precisely, these people demanded the immediate and complete freedom of all slaves.

The majority of the early abolitionists were white, religious Americans, but some of the movement's most notable leaders were also Black people who had fled from slavery.

Therefore, Abolitionists fought for racial segregation, and they were black freedom fighters.

To learn more about the Abolitionist Movement, click here:

https://brainly.com/question/9741757

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what effect did the embargo of 1807 have on manufacturing in the united states?

Answers

Answer:

C. stimulated its growth

Explanation:

Answer

When was the Eastern Orthodox church founded?​

Answers

Answer:

The Eastern Orthodox Church was founded in Judea.

which of these does uruguay export more than fish?

Answers

Answer:

Beef

Explanation:

Answer:

beef

Explanation:

i got 100

what is the height of mount Everest (sagarmatha)? in which place is it located?​

Answers

Answer:

the exact height stands about 29,032 ft, and is located in the Himilaya mountain range

Explanation:

"Mount Everest is a peak in the Himalaya mountain range. It is located between Nepal and Tibet, an autonomous region of China. At 8,849 meters (29,032 feet), it is considered the tallest point on Earth. In the nineteenth century, the mountain was named after George Everest, a former Surveyor General of India."

How the government should be, why we should abide with federalism?

Answers

DEFINITION :-

Federalism provides a way for different groups of people in different parts of the country to live together. ... Federalism provides ways by which these different groups share power over common interests, but it also provides for these groups to have a level of autonomy vis-à-vis central state institutions.

KEY FEATURES OF FEDERALISM:There are two or more levels (or tiers) of government. Different tiers of government govern the same citizens, but each tier has its own jurisdictionin specific matters of legislation, taxation and administration.

In a short paragraph, describe two examples of
how changes to the railroad helped American
industries to grow.

Answers

Answer:

Read Below:

Explanation:

Two examples of how changes to the railroad system helped American Industries to grow is first the expansion West.

When the railroad was made, it made the Western Coast much more important, as both sides were linked with a reliable way of transportation. As a result of this, Industries from both coasts benefited as you could manufacture some parts in California and bring it to Georgia to make a product.

Another example of how the change benefited industries is how it made commerce avaliable large scale. The benefits of this also helped both coasts of the USA.

Answer:

Railroads made it easier for people to travel long distances. They also helped many industries grow. The iron, steel, coal, lumber, and glass industries all grew partly because the railroads needed their products. Railroads also increased trade among cities, towns, and settlements.

Explanation:

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