if photons are massless, how can it push something like a light sail, and how can sunlight adds weight to earth?

Question

if photons are massless, how can it push something like a light sail, and how can sunlight adds weight to earth?

In: 2

Answer 1

Photons are weird, since they move at the speed of light, we’re into relativity which allows odd things like being sort of a wave and sort of a particle and having momentum but not mass, like a photon.

I won’t try to properly explain it, I can’t, I just want to get across the idea that as you approach the speed of light the Newtonian physics we all cover in high school fall apart. Einsteinian relatively and subsequent work building on it lets us theorize and make more accurate observations near or at the speed of light and it’s a different rule set.