If I have solid rod several light year long and I push one of the ends. How long will it take for the other end to be pushed?

Question

Will it take years for the “movement” to be felt from the other end?

In: 19

Answer 1

The motion of the everything moves via a vibration wave… think of a spring on a microscopic level. If the rod is hardened steel, the speed of sound is 3150 m/s. On light year is 9.46×10^15 meters. Assuming the rod didn’t just absorb that vibration and convert the energy to heat, it would take about 95,000 years for the other end to feel it.

https://www.rshydro.co.uk/sound-speeds/