- #1
fbs7
- 345
- 37
I think I understand how electromagnetic force works, so I predict that if I take a big, big, long flat table, charge that table with a big negative electric voltage (say -500kV), then I shoot an electron at that table at an angle, then the electron will be repulsed by the charge, will make a nice little parabola and then shoot out at an outbound angle equal to the inbound angle, all the while following a nice smooth trajectory. If you watch that from a billion km away, the parabola part becomes very small and the electron will just seem to bounce off the the table - but it actually never touches it.
Now, instead of an electron, if you remove the electric charge from the table and shoot a ping-pong ball at the table, it will also seem to bounce off the table at the same angle, but it's actually not touching it either. I understand that electromagnetic repulsion between the ping pong atoms and the table atoms will act exactly the same way (although with a different formula, as that's repulsion between atoms, and is quantum level rather than classical), so the force here is also electromagnetic.
Then if my table is a mirror and I shoot a ray of light... which force is responsible for the photon emerging at the same exact angle at the other side? It can't be electromagnetism, as light does not interact. The only things I know a photon can do is to follow a straight line (bent by gravity), be absorbed by a particle and be emitted by a particle... so is the photon being absorbed by the atoms in the table and then, somehow, another photon is (magically) re-emitted at the same exact angle that it arrived?
Now, instead of an electron, if you remove the electric charge from the table and shoot a ping-pong ball at the table, it will also seem to bounce off the table at the same angle, but it's actually not touching it either. I understand that electromagnetic repulsion between the ping pong atoms and the table atoms will act exactly the same way (although with a different formula, as that's repulsion between atoms, and is quantum level rather than classical), so the force here is also electromagnetic.
Then if my table is a mirror and I shoot a ray of light... which force is responsible for the photon emerging at the same exact angle at the other side? It can't be electromagnetism, as light does not interact. The only things I know a photon can do is to follow a straight line (bent by gravity), be absorbed by a particle and be emitted by a particle... so is the photon being absorbed by the atoms in the table and then, somehow, another photon is (magically) re-emitted at the same exact angle that it arrived?