0 Members and 1 Guest are viewing this topic.
Simple question. I understand that force is (according to wikipedia) "anything that can cause mass to change its velocity",
So gravitational force exists, but when do you call it energy and not force? This is what I'm confused on (or rather, that's my focus.. I'm confused on most of this)
About the light question, the wording confused me a bit... the main thing that stood out was the correlation between your question and your username =P. What do you mean "does it make a force on the beam"?
Basically force and energy is same thing=== matter motion/function result,,but i think that different is that force we can hmm.see directly,,like mechanical motion,,it is quite clear,,but motion which is non-clear like electricity motion or heat-energy,,and therefore we use word energy and so on.
Since the mirror has recoiled, light must have made a force on it; then, in the same way, the mirror should have made a force on the light beam!
Quote from: lightarrowSince the mirror has recoiled, light must have made a force on it; then, in the same way, the mirror should have made a force on the light beam!The light beam then must be changed in some way after the impact with the mirror. I suspect it would be wave-length shifted slightly toward the red. 
Alright I think I get it, all in all. Thanks for clarifying the definition of force for me.Although the velocity only changes from +c to -c if it comes to the mirror head-on, doesn't it?