Recent content by physics2460

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    How well can you know the momentum of the electron?

    Ok, here what we know so far: 1. the electron has angular momentum. 2. But only certain values of angular momentum which are multiples of Plank's constant. 3. the combination of quantized energy and quantized angular momentum picks out only certain allowed orbits 4. so: the wavefronts...
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    If we see wavelengths from 0.4 mm (blue) (not 400nm) and 0.7 mm(red) (not 700nm)

    Thanks for the explanation. It really helps. You see my task is to just imagine what the world would look like if the IR light has regular visible spectrum colors and we see it as a regular visible spectrum, provided that the world remains the same. I have to slide or shift my vision to longer...
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    If we see wavelengths from 0.4 mm (blue) (not 400nm) and 0.7 mm(red) (not 700nm)

    So a blackbody radiator at room temperature would really look black to us (using our normal eyes...not the IR seeing ones postulated in the OP). But it would be glowing in the infrared. In fact, most room temperature objects (including you or me) ARE glowing in the infrared, even though we...
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    If we see wavelengths from 0.4 mm (blue) (not 400nm) and 0.7 mm(red) (not 700nm)

    It looks like we will not even be able to see the sun as the wavelength of its radiation will be too short for us to perceive (5 x 10^(-7) m to be exact.) The wavelength for black bodies can be calculated using Wien’s desplacement law: wavelength = b / T where b is a constant (2.9 x 10^(-3) m K)...
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    If we see wavelengths from 0.4 mm (blue) (not 400nm) and 0.7 mm(red) (not 700nm)

    taking a brightness map of everything (i.e. a monochrome bitmap image), and you could assign false colour to it which wouldn't be a "true image" but quite good nonetheless. How would it look? Set the slider on our "everything-scope" to that range and find out. :biggrin: OK, how can I do...
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    If we see wavelengths from 0.4 mm (blue) (not 400nm) and 0.7 mm(red) (not 700nm)

    [Since neither of us likely understands how colour is assigned by the brain based on wavelength, or if the colours are entirely random (i.e. "this shade" = "this wavelength" instead of "shade = f(wavelength)") and share no relation with wavelength, do we have a hope of answering that? Humans can...
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    If we see wavelengths from 0.4 mm (blue) (not 400nm) and 0.7 mm(red) (not 700nm)

    Is there any ONE mechanism that can do that? You have x-ray machines, electron microscopes, IR imagers, visible microscopes, radio telescopes - but can one single "thing" do that? What properties would be needed? For the opposite (emission), you would need a material with a variable work...
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    If we see wavelengths from 0.4 mm (blue) (not 400nm) and 0.7 mm(red) (not 700nm)

    Dear mgb_phys, let's try it one more time, here's what I understood: if we see only the wavelengths that range from 0.4 x 10^(-3) m to 0.7 x 10^(-3)m (o.4mm to 0.7 mm) that means that we can't see visible light that is reflected off the objects around us. We also cannot see human bodies even...
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    If we see wavelengths from 0.4 mm (blue) (not 400nm) and 0.7 mm(red) (not 700nm)

    mgb-phys: thanks so much. But look what I found on wikipedia: We will not see human bodies because at a temperature of 37 degrees C, our bodies radiate with a peak intensity near 900 nm (9 x 10^(-7) m) which is much shorter than what we can see with our new ability to see long infrared light...
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    If we see wavelengths from 0.4 mm (blue) (not 400nm) and 0.7 mm(red) (not 700nm)

    Hello everyone, here's a question that I have: Imagine your eye was sensitive in wavelengths of 0.4 mm to 0.7 mm rather than 400 nm to 700 nm. In this case, your mind would identify light waves that were 0.4 mm as blue and 0.7 mm as red. What would your world look like? How would it be...
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    Clocks on spaceship travelling at the speed of light

    I totally agree with you, guys. But I think we should let it go. It was the only question that I ever asked on the forum since the beginning of the semester. I did pretty well learning that far on my own. Thanks for the answer and the advice. However, Dave's condescending tone was totally...
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    Clocks on spaceship travelling at the speed of light

    clocks on the ship question Bill I apprecialte your help so much, Thanks, Dina
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    Clocks on spaceship travelling at the speed of light

    Dear DaveC426913, I don't understand why it bothers you so much, or maybe I do understand a little. I've been doing fine in my physics class and had lots of success on my weekly quizes. But it's the end of the semester and I thought I was lucky I found you, guys, because, sometimes it's...
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    Clocks on spaceship travelling at the speed of light

    Homework Statement Hi guys, I'm in a Physics for poets class? Could you , please, help me with these questions? Suppose you are watching a spaceship go past you toward the right at close to the speed of light. 1. How do the clocks on the spaceship appear to run compared to your own clock...
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