Where on Earth can you travel directly East one kilometer and end up in the exact place you started?

Question

This is not a trick. It can be done - in more than one place.
Check back after someone gets it right to see how it can be done.

Answer 1

There are in fact an infinite number of places this can be done.

Near either pole is degree of latitude where the entire way around is 1km. A bit closer to each pole is a latitude where it is .5 kms.
Even further there is one where it is exactly one third of a km.
Just keep going where the entire way around the world is 1/x kms where x is an integer this can be done. x has not upper limit so there are an infinite number of places.

Answer 2

Very close to the north pole, where the circumference of the earth is just 1 kilometer. Going east means following the latitude lines, going around the pole in this case - and if that distance is just a single kilometer, after you travel a kilometer you'll be back where you started. It also works near the south pole, in the same way.

Answer 3

There are two places where this can be done, 1.57079633 Km north of the geometric south pole, or the same distance south of the north pole.

The reasoning behind this is that those points lie on a circle whose diameter is 1 Km.

The circumference of a circle is c = 2πr
We know that c = 1 Km, so
2πr = 1
r = 1 / 2π
r = 1.57079633

Answer 4

I would say the north or south poles, but 1 kilometer from your starting point is still one kilometer from your starting point, isn't it? Unless you're moving in a circle, and that's not directly East. Oh, wait a minute, yes it is, if your walk takes you 24 hours. Or not. Oh well, I tried.

Answer 5

At a latitude very close to the North or South pole. The circumference of your circular walk would be exactly one km.

Answer 6

Just slightly away from either the north or south geographic poles.
At the north pole, all directions are south. There is no east or west. Likewise, at the south pole, all directions are north.

Answer 7

The North Pole or in case you have been on precise of Mount Everest or any large mountain with a top as once you flow down one mile then flow around one mile and flow back up one mile you will possibly nevertheless finally end up back on the top.

Answer 8

If we want to make a 1.0 km circle (near the north or south pole) along a line of latitude, then the radius of that circle needs to be

C=2πr
r=C/(2π)=(1.0 km/2 π)=0.16 km

For chord distances much smaller than the radius of the circle (R=6373 km for the Earth), the chord distance and the arc distance are about the same.

d=r=0.16 km

Answer 9

around the north and south poles, where the circumference of that portion of the earth is 1km or can divide evenly into 1km (ie, 500 meters)

Answer 10

Hi. I'll bet it's right near the north and south poles. Just about .5km / pi away.