# Somebody is living on a spherical world

• kleinwolf
In summary, the problem is asking for the radius of a spherical world based on the information that a circle of radius 1m can be drawn with a rope without circumventing the sphere. There are two possible worlds in this situation and it is possible to find the radius of the sphere by using the rope as a compass.
kleinwolf
Somebody is living on a spherical world. He is drawing a circle of radius 1m with a rope. We know there are only 2 possible worlds.

What is the radius of this world knowing the rope cannot circumvent the sphere ?

kleinwolf said:
What is the radius of this world knowing the rope cannot circumvent the sphere ?

which world are you exactly talking about.

and can you please elaborate on the 2 worlds.

The problem has insufficient information with which to define an answer.

Well, except for a meta-answer, as in: any of an infinite number of worlds whose circumference is > 1m.

Yes you're right : the guy tells us the perimeter of that circle of 1m radius. We know this and the fact (by another source of information) that there are only two possible worlds.

I think I might know what kleinwolf means, but I am too lazy right now to get the answer. Here is a possible meaning to the puzzle:

First of all, I think he means to use the rope as a kind of compass, as you might use to draw a circle on a flat piece of paper. There are two ways to do this on a sphere without breaking through the sphere. One is to stretch the rope taut around a great circle of the sphere. The other is to stretch the rope straight on the inside of the sphere. I assume (because the problem is probably solvable), that for a given length of rope, there is only one radius for the sphere that allows these two drawn circles to have the same radius. Thus, there is only one radius for the sphere that would allow the radii of the circles to be 1m.

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## 1. How do we know that somebody is living on a spherical world?

Scientists have gathered evidence from various sources, including satellite images, observations of the stars and planets, and mathematical calculations, that suggest the Earth is indeed spherical.

## 2. Is it possible for someone to live on a spherical world?

Yes, it is possible for someone to live on a spherical world. In fact, we are already living on a spherical world - the Earth. The spherical shape of the Earth allows for gravity to keep everything in place and for life to thrive.

## 3. How does living on a spherical world affect our daily lives?

Living on a spherical world affects our daily lives in many ways. For example, it causes the day and night cycle, the changing of seasons, and the tides. It also affects navigation, communication, and the distribution of resources.

## 4. Are there other planets or celestial bodies that are also spherical?

Yes, there are many other planets and celestial bodies that are also spherical. In fact, most objects in space with enough mass to exert gravitational force are spherical in shape. This is due to the force of gravity pulling everything towards the center of mass.

## 5. How does the spherical shape of our world impact our understanding of the universe?

The spherical shape of our world has greatly impacted our understanding of the universe. It has allowed us to accurately map and study the Earth's surface, as well as make predictions and calculations about other celestial bodies. It has also helped us to understand the concept of gravity and its role in the formation and movement of objects in the universe.

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