How light can bounce off objects but it has no mass.

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I understand that light has momentum but if it has no mass how can it bounce?

In: Physics

3 Answers

Anonymous 0 Comments

Light does not “bounce.” A photon of light is absorbed by an atom, which excites an electron in that atom. The electron then relaxes, which causes the atom to give off (or emit) a photon of light.

Think of it more like a person catching and then throwing a ball, as compared to a ball bouncing off of a wall.

Anonymous 0 Comments

You know how magnets can repel each other? The forces inside atoms are waaaaay stronger than that. In fact, they’re so strong they can literally bounce incoming energy, like light, away. After all, all mass is just energy. E = mc^2 shows us that mass is a LOT of energy.

Anonymous 0 Comments

It is being reflected, not “bounced” per se. It is reflected, it has a momentum but no mass, but energy. energy = Planck’s constant / impulse.