[Closed] Physicists - a hard one

You're thinking of photons as particles. You need to think about them as wave energy....

If they are waves, do they bounce off things like waves do on rocks?

Surely then when the waves from the lightbulb hit me I would see the lightbulb and then the waves would bounce off me to someopne else who would look at me and see a lightbulb?

WorldClassAccident - Member

If they are waves, do they bounce off things like waves do on rocks?

Surely then when the waves from the lightbulb hit me I would see the lightbulb and then the waves would bounce off me to someopne else who would look at me and see a lightbulb?

Only if you are a mirror

druidh - Member

WorldClassAccident - Member

If they are waves, do they bounce off things like waves do on rocks?

Surely then when the waves from the lightbulb hit me I would see the lightbulb and then the waves would bounce off me to someopne else who would look at me and see a lightbulb?

Only if you are a mirror
druidh - Member

WorldClassAccident - Member

If they are waves, do they bounce off things like waves do on rocks?

Surely then when the waves from the lightbulb hit me I would see the lightbulb and then the waves would bounce off me to someopne else who would look at me and see a lightbulb?

Only if you are a mirror

And you are standing on a treadmill.

They do bounce off you, that's how we see - reflected light. No light, no see 🙂

Only if you are a mirror

...or a light bulb

The real question should be, how many lightbulbs will there be at BBB?

Start googling wave-particle duality 🙂

Not a physicist but from laymans perspective photons can be thought of as emitted radiation in the form of packets. Only a fixed number are made, they spread out from their source. Think of them like shrapnel in a grenade - more people looking doesnt make the damage to anyone else any less. By the time you're a mile away you'd be lucky to get hit by a shard (or a photon) so you bearly see the source, unless its mega bright or a laser pointed at your eyes (lasers are just coherent sources of photos all moving in one direction. Then things get a bit confusing, if you fire light at a small crack it'll act like a wave rather than particles- with ripples of constructive and destructive interference (light and dark spots). Its fascinating but possibly too much for a tinterweb forum.

What coffeking said. In terms of 'seeing' light is focussed by the lens onto a point on your retina called the fovea which has cells (rods and cones) sensitive to light. Some are specialised for colour vision (cones) and others for low light conditions (rods). They detect the light, send an electrical signal via the optic nerve to the brain, which deciphers the messages and interprets it as an image.

As you move away from the source it is reduced in intensity by a cube of the distance by the way, i.e. double distance from source intensity falls by 8 times

Again, what coffeeking said.

joe1983, I think you mean square of the distance, not cube...

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It's early onset alzheimers

Mine sets in about half past three every afternoon...

Don't forget the biology folks 😉

Do more people looking absorb more photons?

Yes. We call these things shadows Dougal.

For the purposes of explaining light from a light bulb, classical theory of light is sufficient: Light is emitted from the bulb as a wave - lots of waves in all directions. The wave you see is not the same as one the person next to you sees...

Photons are part of Quantum mechanics, which should be left for the 'really hard one for physicists' thread

If they are waves, do they bounce off things like waves do on rocks?

In a sense, yes. Its called diffraction (not to be confused with refraction or reflection). Diffraction is why you see some light when sitting in a dark room with the light on in the hall - the light is diffracted by the edge of the door/door frame.

But diffraction intensity is week, so you don't see it in a normally lit room.