Extending to Space?

Question

I thought of this question suddenly when I was bored.

Imagine having a very long metal rod, so long that it's about the diameter of the Earth. If I place the metal rod in front of me, parallel to Earth's surface, wouldn't it be like a tangent to a circle, and the rod would extend beyond the Earth's atmosphere and to space?

Some might say that the rod will bend downwards and never extend to space.

But what if I had a extremely powerful laser, of which its beam is very visible (think the Death Star laser), and shine it parallel to the Earth's surface? Would it extend to space? If it bends, then it contradicts the fact that light cannot bend (yes I know it can bend under certain circumstances, but definitely not now).

Just a few thoughts.

Answer 1

Darren -

If I understand your question, then you are correct. The rod is deceiving, because the weight of the rod itself would cause the rod to bend severely before it got to the next block, much less outer space. However, if you assume a rod with infinite stiffness and no mass, then you could extend it along the surface of the earth in any direction. As the surface of the earth falls away due to its curvature, the rod would extend in a straight line out into space. If it was long enough, you could reach out and touch the moon as it rises or sets.

The laser has its own set of complications. Sure, it would reach outer space - but it would not be perfectly straight. It would bend slightly due to refraction as it leaves the denser atmosphere, and it would also bend slightly due to the earth's gravitational field. These are small effects, but not zero.

Answer 2

The laser would still bend if only slightly but neglecting that, what's your point?

Answer 3

The purpose of the holiday is to circle around and around the Earth, not pass quickly faraway from it. with a view to circle the Earth the holiday desires some thank you to offset the tension of gravity it is consistently attempting to pull it back off and does this via moving rapid sufficient perpendicular to the tension of gravity.