Imagine you have a very long belt. Well, extremely long, really ... in fact, it's just long enough that it can wrap snugly around the circumference of our entire planet. (For the sake of simplicity, let's suppose Earth is perfectly round, with no mountains, oceans, or other barriers in the way of the belt.) Naturally, you're very proud of your belt. But then your brother, Peter, shows up-and to your disgruntlement, he produces a belt that's just a bit longer than yours. He brags his belt is longer by exactly his height: 6 feet. If Peter were also to wrap his belt around the circumference of Earth, how far above the surface could he suspend the belt if he pulled it tautly and uniformly?

Question

Mathematics

Simeon Weiss

3 February, 08:49

Imagine you have a very long belt. Well, extremely long, really ... in fact, it's just long enough that it can wrap snugly around the circumference of our entire planet. (For the sake of simplicity, let's suppose Earth is perfectly round, with no mountains, oceans, or other barriers in the way of the belt.) Naturally, you're very proud of your belt. But then your brother, Peter, shows up-and to your disgruntlement, he produces a belt that's just a bit longer than yours. He brags his belt is longer by exactly his height: 6 feet. If Peter were also to wrap his belt around the circumference of Earth, how far above the surface could he suspend the belt if he pulled it tautly and uniformly?

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Answers (2)

Know the Answer?

Alison Levy · Answer 1

H = 0.95 feet

Step-by-step explanation:

The circumference of Earth = 2πR

My belt = 2πR (Where R is the radius of the Earth)

Peter's belt = 2πR+6

We have to find the Height "h" so the radius of the circle for Peter's belt becomes R+h So the expression becomes 2π (R+h)

But we already know,

Peter's belt = 2πR+6

So,

2πR+6 = 2π (R+H)

2πR + 6 = 2πR + 2πH

Subtracting 2πR to both sides

=> 6 = 2πH

OR

=> H = 6/2π

=> H = 3/π

Where π = 3.14

=> H = 0.95 feet

Myles Blackwell · Answer 2

Answer: 0.00016 miles

Step-by-step explanation:

According to Google, the circumference of the Earth is 24,901.461 miles. Using the formula 2*pi*r = circumference, the radius of your belt is around 3963.19061 miles. Now, 6 feet is 0.001 miles. So his belt is 24,901.461+0.001 = 24,901.462 miles. Use 2*pi*r to get 3963.19077 miles, a full 0.00016 miles above the surface!