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How do photons travel so fast? Is there a way to stop them?
Question Date: 2011-08-02
Answer 1:

Photons in a vacuum, like all electromagnetic radiation, travel at the speed of light about 300000 km/s, but its very easy to stop a photon!! Just go out into the sunlight, and hold your hand up... photons emitted from the sun a mere 8 mins ago will strike your hand... the photons will stop moving and give their energy to you... your hand heats up!!

Answer 2:

Photons move at the speed of light because they have no inherent mass to slow them down. Because they have no inherent mass, they can't really be stopped per-se, because a photon that wasn't moving would have no basis to even exist - really all a photon is depends on its movement. They can be absorbed, however, in which the photon strikes something which then takes up its energy.

Answer 3:

There's a link below about stopping photons. I like the title: "Sit! Speak! Good Photon!" I thought photons stopped when they were absorbed by something dark, like how less light gets through the window after you pull down the shade. But it seems to be more complicated than that.

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