Difference between black and transparent object

In summary, black objects are black because they absorb all the wavelengths of light. Transparent objects are also black, as they don't reflect any light.
  • #1
gracy
2,486
83
Difference between transparent and black object?I mean black object is black because 1-it absorbs all the wavelengths of light OR 2-because it doesn't reflect any wavelength of light
If first one is the reason then alright but if second one then transparent object should also be black as it does not reflect(reflects only 5%)it all transmit (about 95%)
 
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  • #2
Black objects don't transmit light either, they absorb light. That's why you can't see through them. :)
 
  • #3
Matterwave said:
Black objects don't transmit light either, they absorb light. That's why you can't see through them. :)
Why black objects are black?Because of reason 1 in my original post?Not because of reason 2?
 
  • #4
If you look at a transparent object, you see not only the light reflected from it, but also the light coming from behind and transmitted by the object.
 
  • #5
ehild said:
If you look at a transparent object, you see not only the light reflected from it, but also the light coming from behind and transmitted by the object.
Till now i have been told that we only see color of objects depending upon what wavelength they reflect ,do the color of the object also depends on the wavelength which is transmitted?
 
  • #6
Yes. The colour of transparent objects is more the colour of the transmitted light than the reflected one. But it depends also, how you look at them. What colours you see if you look through your sunglasses? And how do they look like in reflected light?
 
  • #7
Water is colorless ,why?Is it transparent?
 
  • #8
gracy said:
Water is colorless ,why?Is it transparent?

It can be described as transparent but, in reality, even a thin layer of water does absorb some of the of light (some wavelengths more than others) , which you can detect if you go diving in ('clear') water of more than 10m or so. The Red end of the (visible) spectrum is absorbed more than the Blue end and objects will look generally 'bluer'. your brain does its best to compensate for this but, in the end, you just seem to see things in 'monochrome'.
As it happens, UV is absorbed too. The absorption / frequency characteristic is complicated with various peaks and troughs (See this wiki link) because of the way the water molecules interact with various frequencies of WM waves.
 
  • #9
gracy said:
Till now i have been told that we only see color of objects depending upon what wavelength they reflect ,do the color of the object also depends on the wavelength which is transmitted?
A very thin gold leaf, viewed in reflected light, appears golden because it reflects the yellows and reds especially well. But if you hold it up against a bright light, it appears green. Being very thin it allows some light to pass through, and this transmitted light is white minus the colours it reflects on the other side.
 
  • #10
gracy said:
Till now i have been told that we only see color of objects depending upon what wavelength they reflect ,do the color of the object also depends on the wavelength which is transmitted?

Yes. Objects can be transparent to some wavelengths and not others. A red filter (eg for stage lighting) allows red light through and absorbs other colours. The result is that only red light illuminates the stage. If you look at the filter with a white light behind it only red light arrives at the eye so it looks red.

The plastic on a TV remote control is opaque to visible light but it is transparent to invisible infra red light so it can control the TV. The plastic is usually back but could be any colour. So it can be transparent to Infra Red, opaque to visible light but reflect any or all visible light.
 
  • #11
Very thin lays of very transparent materials can produce very intense colours by reflecting some wavelengths and transmitting others. There is (virtually) no absorption of energy within the layers all the light is either reflected or transmitted. (Interference Filters)
Examples: Bird Feathers, Butterfly wings, Dichroic halogen lamps, which do not use pigments or dyes. Most familiar example is the bright colours from oil films on puddles of rainwater. Notice the colours are not 'rainbow-like' but very striking and unusual.
 

What is the difference between a black object and a transparent object?

A black object absorbs all light that hits it, while a transparent object allows light to pass through it.

How does the color of an object affect its transparency?

The color of an object is determined by the wavelengths of light that it reflects or absorbs. Transparent objects typically reflect or absorb all wavelengths of light equally, while black objects absorb all wavelengths of light.

Why do some objects appear black while others appear transparent?

Objects appear black because they absorb all light that hits them, while objects appear transparent because they allow light to pass through them. This is determined by the material and structure of the object.

Can an object be both black and transparent?

Yes, some objects can have both black and transparent properties. For example, a tinted glass window may appear black from the outside due to its ability to absorb light, but still allow light to pass through it from the inside.

How does the thickness of an object affect its transparency?

The thickness of an object can affect its transparency by influencing how much light is able to pass through it. Thicker objects typically block more light, while thinner objects may allow more light to pass through.

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