Assume the earth is 25k miles circumference at the equator and is perfectly smooth. Then a transmission cable laid on the ground and circling the earth at the equator would have a length of 25k miles. Now suppose we want to provide a 1 foot line to ground clearance all the way around the earth.
Assuming no sag, approximately how much extra cable would be required?
- 6.3 ft
- 28.4 miles
- 3.14 ft
- 12.5 k miles
- none of these. See my answer below