Tim Z. answered • 05/22/24
Aerospace Engineer to Help With Math or Physics
To start, we need to discuss how we perceive light and what light is. Light travels in the form of particles called photons. Although photons are particles, they can exhibit certain wavelengths. The wavelength is what determines how the photon behaves, whether it's an X-Ray, Ultraviolet Ray, Infrared Waves, or in the case we're looking at, visible light! Purple light has a wavelength has small as 380 nanometers, and red light has a wavelength as large as 700 nanometers. All the other colors are in between in order of the rainbow.
The way we perceive an objects color, depends on what light it absorbs and reflects. For example, a red ball absorbs all visible light except light with wavelengths of 700 nanometers. A tree's leaves absorb all light except light waves with a wavelength of 560 nanometers (wavelength of green light). So the photons will hit the object, and only a certain wavelength will bounce off, In the case of a red ball, red wavelength light, and the red-wavelength light will hit our eyes, and we perceive the ball as red.
The special thing about a mirror, is it reflects all light! So let's say we hold that red ball in front of the mirror. We can see the red ball in our hand, but also in the mirror. What's happening is some photons bounce off of the red ball and go directly into our eye, and some bounce off of the red ball, hit the mirror, and then into our eye. This is how we can see the red ball in both our hand and in the mirror.
If you'd like any more info like angle of incidence, reflection, refraction, absorption, or more, feel free to ask!
Hailey P.
Does the object actually “do” anything like when you say reflects and absorbs is that actually the object doing that?05/22/24
Leo W.
The object is "doing" the reflecting and absorbing of light (the molecular structure and various surface features of the object). The reflected light then bounces off the mirror and/or travels to our eyes. In the process it CAN conceivably have SOME effect on the object that it is reflecting off or absorbed by, but generally visible light doesn't alter objects much (maybe a laser would). Taking a picture happens AFTER the light has left the object so is not going to affect the object except in some quantum mechanical sense.05/23/24
Tim Z.
Great questions! We'll start with the second one first. Short answer, yes! The electrons react to the photons hitting them. Looking closer on the atomic level, we have to look at the structure of an atom. An atom consists of a nucleus made of protons and neutrons, and electrons orbiting the nucleus at different energy levels. Let's look at that red ball again. When white light hits the red ball, the some of the photons are absorbed into the atoms. More specifically, the photon's energy are imparted into the electrons of the atoms to excite them, which can increase vibrational energy of the atoms. However, it takes a very specific energy to excite an electron. Photons that cannot excite the electrons of the atom are reflected away. So if a red ball absorbs all photons but ones with red wavelengths, that means the electrons in the dye of the ball can be excited by all wavelengths of visible light except photons of red wavelength. Those photons are reflected away, hit our eyes, and that's how we receive the red ball. Silver, the material first used in mirrors, is a great reflector because very few wavelengths can excite the electrons in the atoms of the silver, meaning most of them will reflect. Depending on the purity of the metal, silver can have a reflectivity of 65%-99%! So when you mean ruin, do you mean distorting the image of the object? Like the red ball would look different in the mirror than in your hand? In that case, no, a mirror would not distort the image of anything in the mirror, as long as the mirror is completely flat. If the mirror were rounded or curved in any way, it would distort the image. This is what causes your face to look funny in the reflection of your spoon. Until very recently, cameras and videos had very, very slight distortions of images, since we could not figure out how to create a lens to perfectly capture an image, but as of a few years ago we figured it out. However, those distortions aren't really noticeable to the human eye. If I didn'tanswer the first question, please clarify and let me know!05/23/24
Hailey P.
So does the solid object itself - in this instance the ball do anything? Like does the ball itself absorb and reflect, or is that really the atoms and molecules that make up the solid. (for example: atoms and molecules vibrate in a solid, but the solid object itself does not move or vibrate) so does the ball actually do anything? Also, I guess I mean does light damage an object? Does taking a photo or a video of an item damage it? Does allowing the reflection in the object in the mirror- can it cause any damage to the object itself?05/23/24
Hailey P.
So does the solid object itself - in this instance the ball do anything? Like does the ball itself absorb and reflect, or is that really the atoms and molecules that make up the solid. (for example: atoms and molecules vibrate in a solid, but the solid object itself does not move or vibrate) so does the ball actually do anything? Also, I guess I mean does light damage an object? Does taking a photo or a video of an item damage it? Does allowing the reflection in the object in the mirror- can it cause any damage to the object itself?06/03/24
Hailey P.
Wait, so does the object itself actually physically do something when light is reflected or refracted on the item to show the item color? Like for instance a red ball? Is the object itself physically doing anything?06/21/24
Hailey P.
So quick question - does the light ruin an object or the reflection of a mirror on an object, or a camera? Like taking a picture or videoing the object?05/22/24