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Tdworld 3408 Tapemeasure
Tdworld 3408 Tapemeasure
Tdworld 3408 Tapemeasure
Tdworld 3408 Tapemeasure
Tdworld 3408 Tapemeasure

Solve This: Going to Any Lengths

Oct. 26, 2015
Here's a little puzzle to ruminate on during a coffee break. Maybe you'll win a gift card! Give it your best shot in the comment section below. Enter as many times as you want. A $50 gift card will go to the first right answer. We need your email to send the gift card so make sure you're registered (and you have verified your registration via email) when you leave your comment in the box below. We cannot send you a gift card without completed verification (answer the email that asks you to click through to verify)

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

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