3 ms·
My intuition is failing me here. How does that work since there is no body of water like a boat has to push off?
by jahnu 2y ago
My intuition is failing me here. How does that work since there is no body of water like a boat has to push off?
- zardo 2y agoThe sail is a mirror. Subtract the momentum vector of the incoming light from that of the reflected light and you have the momentum change applied to the sail.
- teraflop 2y agoIt's true that the mechanism is different, but this still works (to a limited extent) even without any external object to transfer momentum to, just using the momentum of the photons themselves. I can't be bothered to draw a diagram, but imagine that the sun is to the "north", and the solar sail is at a 45-degree angle running NE/SW. Incoming photons heading south reflect off the sail and leave to the west. So the photons experience a net momentum change to the NW, pushing the sail to the SE, which is not directly away from the sun.
- jahnu 2y agoThanks, that makes complete sense!