Physics Thought Experiment and Question

[PHC1]

Originally Posted by crwilli

I thought mass approaches infinity at the speed of light? E=MC2?

In classic physics, the mass of the needle would mean very little, even if it was moving at 300,000,000 m/s

The mass of a needle is around 1 gram, or around 0.001 kg.

The mass of our planet is 5.9 x 10^24 kg.

Conservation of momentum: the two bodies with such a mass difference would be insignificant. The Earth would neither budge nor even blink.

Quantum physics, watch out!

"Momentum" of the needle would be infinity at the speed of light. Bad news for Earth. Game over!

Good thing objects with mass can not travel at the speed of light... As far as we know!!!

[crwilli]

. I suppose I should have known simply by considering the equations that govern classic physics.

[PHC1]

Originally Posted by crwilli

. I suppose I should have known simply by considering the equations that govern classic physics.

Somewhere, deep under the dirt layer, there is a dinosaur that is turning in his grave right now. It wasn't a needle and it wasn't traveling at the speed of light but it was enough to wipe them all out and probably most of the other species of animals.

"When an asteroid or comet slammed into Earth about 66 million years ago, most of our planet’s species were wiped out in a mass extinction—including entire groups such as the nonavian dinosaurs, marine reptiles such as mosasaurs, and their flying kin the pterosaurs. But not all ecosystems suffered equally, and the dramatic difference in survival rates between marine species and freshwater ones has been particularly puzzling. A new study weighs in on the long-standing riddle." https://www.sciencemag.org/news/2013...e%20pterosaurs.

[radio times]

Someone did a vid on the 'tube about this. The 1g at speed of light would destroy the earth and a chap would bounce up and down like a ping pong ball if he tried to build a tunnel to the centre of the earth.

[clpetersen]

Well ignoring all the esoteric effects, the simple object would eventually feel the pull of the moon, just like the tides do.