Why can an infinite area have a finite volume or SA?

In summary, the concept of Gabriel's Horn is a mathematical shape with infinite surface area but finite volume. It is often used as an example to demonstrate the paradoxical nature of infinity in mathematics. The shape can be generated by removing an infinite sequence of slices from a cube, resulting in a shape with the same volume but infinite surface area.
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Zack K
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I have a calculus 2 midterm coming up and given the exam review questions, this seems like this question can potentially be on it.

I've tried to look it up, but I always find the famous painters example, which I don't find satisfying.
 
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Google Gabriel's Horn
 
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Likes Zack K and jedishrfu
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Zack K said:
I have a calculus 2 midterm coming up and given the exam review questions, this seems like this question can potentially be on it.

I've tried to look it up, but I always find the famous painters example, which I don't find satisfying.

If you think of a cube, you can imagine it as a stack of an infinite number of square surfaces. So, there already is an infinite surface in there, so to speak. A simple way to generate an infinite surface area is simply to remove an infinite sequence of slices: if the cube is 1 unit high, you could remove the slices at ##z = 1/2, 1/3, 1/4 \dots##.

This would leave a shape with actually the same volume as before, but an infinite surface area.
 

Related to Why can an infinite area have a finite volume or SA?

1. Why is it possible for an infinite area to have a finite volume?

This is possible because the concept of infinity is an abstract mathematical concept that does not necessarily correspond to physical reality. In mathematics, we can imagine infinite areas or volumes, but in the physical world, there are always limits and boundaries.

2. How can an infinite area have a finite surface area?

This is because an infinite area does not necessarily mean an infinite surface area. For example, a circle has an infinite number of points in its area, but a finite circumference and surface area. This is due to the fact that the circumference of a circle increases at a slower rate than its radius.

3. Can you give an example of an object with an infinite area and finite volume?

Yes, a fractal is a geometric shape that has an infinite area, but a finite volume. Fractals are self-similar patterns that repeat at different scales, and as the scale gets smaller, the area increases infinitely but the volume remains the same.

4. How does the concept of infinity apply to real-world objects?

The concept of infinity is often used in mathematics to describe idealized objects or processes. In the real world, there are always limitations and boundaries, so the concept of infinity is not applicable in a physical sense. However, it can be a useful tool for understanding and describing certain phenomena.

5. Is it possible for a finite area to have an infinite volume?

No, this is not possible. In order for an object to have an infinite volume, it would need to have an infinite number of points in its area, which is not possible for a finite object. The concept of infinity only applies to theoretical or abstract concepts, and not to physical objects.

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