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The Greek mathematician and astronomer Eratosthenes calculated this in 200 B.C.. He knew that on a particular day in Syene, the sun would be directly overhead. He set up a stick in Alexandria 5,000 stadia away (800-900 kilometres) on this day, and measured the angle of the shadow that the sun formed at midday. He measured this to be 7.2°. He deduced that this is the same angle from the Earth's centre that the distance between the two cities represents. Since there are 360° in a circle, he worked out that 5,000 stadia is one-fiftieth of the circumference of the Earth. He therefore suggested the value of 250,000 stadia (40,000-46,000km). Astronomers recently measured it using satellite equipment and submitted the figure of 40,008 km. From this, using the geometry of circles, he could calculate the Earth's radius: Pretty good for a man who lived 2,200 years ago who only used only a stick!
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Formula to find out the Earth's surface area?
The Earth is close enough to a sphere, so you can use the formula for a sphere: 4 x pi x r2. "r" is the radius; if you find the diameter of Earth somewhere, divide it by 2 to get the radius.The Earth is close enough to a sphere, so you can use the formula for a sphere: 4 x pi x r2. "r" is the radius; if you find the diameter of Earth somewhere, divide it by 2 to get the radius.The Earth is close enough to a sphere, so you can use the formula for a sphere: 4 x pi x r2. "r" is the radius; if you find the diameter of Earth somewhere, divide it by 2 to get the radius.The Earth is close enough to a sphere, so you can use the formula for a sphere: 4 x pi x r2. "r" is the radius; if you find the diameter of Earth somewhere, divide it by 2 to get the radius.
Who invent radius of earth?
If you are a believer, then God did but if you are not, then nobody did. The radius of the earth existed and therefore ots radius did before there was any form of life on earth to invent it.
What is the equation to find the volume of earth?
Where r is the radius of the Earth, and pi = 3.14 (2 decimal places). So, it's 4 thirds multiplied by pi multiplied by the cubed radius of the Earth (6378.1Km average)The best estimate for the Earth's volume is about 1083210000000 cubic km
How do you find the circumference of the earth using the arc length formula?
Just did this in my trig class yesterday. Arc length = radius * theta(radians) Circumference of Earth = radius of earth * 2pi Note: The arc length is the circumference of the Earth only in this case because theta is equal to 2pi.
How do you find the radius if circumference is given?
Divide the circumference by 2PI to find the radius. ( C = 2PI*Radius)
Paul knows the circle of Earth around the Equator but would like to find the radius Find the radius What is the formula?
circumference = 2 x pi x radius radius = circumference/2 x pi
What is Venus' radius as compared to the Earth's?
Venus has a radius of about 6,052 kilometers, which is about 95% of Earth's radius.
Formula to find out the Earth's surface area?
The Earth is close enough to a sphere, so you can use the formula for a sphere: 4 x pi x r2. "r" is the radius; if you find the diameter of Earth somewhere, divide it by 2 to get the radius.The Earth is close enough to a sphere, so you can use the formula for a sphere: 4 x pi x r2. "r" is the radius; if you find the diameter of Earth somewhere, divide it by 2 to get the radius.The Earth is close enough to a sphere, so you can use the formula for a sphere: 4 x pi x r2. "r" is the radius; if you find the diameter of Earth somewhere, divide it by 2 to get the radius.The Earth is close enough to a sphere, so you can use the formula for a sphere: 4 x pi x r2. "r" is the radius; if you find the diameter of Earth somewhere, divide it by 2 to get the radius.
Explain how to get the radius of the Earth?
Find out the circumference and because C=2pi r. then divide the circumference by 2 and the by pi, this leaves you with the radius.
What is the formula for figuring curvature of the earth in any given direction?
The curvature of the Earth in any direction can be calculated using the formula for the Earth's radius of curvature (R), which is given by R = a / β(1 - e^2sinΒ²Ο) where a is the equatorial radius of the Earth and e is the eccentricity of the Earth. By determining the radius of curvature at a specific latitude (Ο), you can find the curvature in that direction.
Who invent radius of earth?
If you are a believer, then God did but if you are not, then nobody did. The radius of the earth existed and therefore ots radius did before there was any form of life on earth to invent it.
What is the radius of earth in kilometers?
The radius of Earth is approximately 6,371 kilometers.
What is the equation to find the volume of earth?
Where r is the radius of the Earth, and pi = 3.14 (2 decimal places). So, it's 4 thirds multiplied by pi multiplied by the cubed radius of the Earth (6378.1Km average)The best estimate for the Earth's volume is about 1083210000000 cubic km
How does Venus compare with the earth radius and mass?
Venus has a radius of 6,051.8 kilometers, which is about 95% of Earth's radius. In terms of mass, Venus has about 81.5% of Earth's mass.
What is Europa's diameter compared to earth?
Europa: 1561 km radius Earth: 6371 km radius The diameter is twice the radius.
How many times greater is the radius of earth compared to Venus?
The radius of Earth is about 0.95 times greater than the radius of Venus.
If radius of mars is 3397km how many times larger is the earth?
Earth's radius is about 6,371 km, so Earth's radius is approximately 1.88 times larger than Mars.
