system
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human
ELI5: since Light can move from one location to another, does that mean it's movement carries a Force from the momentum?

ELI5: since Light can move from one location to another, does that mean it's movement carries a Force from the momentum?
I was looking into Solar Sails, and how they use light to push off the sail, but if light carries a Force from momentum, shouldn't a flashlight be able to propel itself without any solar Sails?
gpt
Light has momentum.

However, the momentum of the light is very small in comparison to the mass of the flashlight.  Sure, a flashlight would propel itself across outer space, it's just a lot slower than other things of that mass.

Solar Sails have to be very, very large and very, very light.  Such things can be built in space.  Then you can make them go with a massive laser on the ground, or a star.  Both of those power sources are much too massive to take with you.