Can MRI Detect a Light Bulb Inside a Closed Box?

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fredreload
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I put a light bulb inside a box and make it glow, is there a way to know where the light bulb is if the box is closed and not transparent
 
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fredreload said:
I put a light bulb inside a box and make it glow, is there a way to know where the light bulb is if the box is closed and not transparent
Sure. What are your thoughts? :smile:
 
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We human have not advance far in science(I have no idea)
 
fredreload said:
We human have not advance far in science(I have no idea)
What is the context of the question? What are the constraints?

Given different constraints, I can think of at least 3 ways of locating the light bulb in the box...
 
Some type of x ray vision? Some kind of imaging technique
 
fredreload said:
Some type of x ray vision? Some kind of imaging technique
Yes, that would be one way. You need to take 3 x-rays to get the full (x,y,z) position.
 
berkeman said:
You need to take 3 x-rays to get the full (x,y,z) position.
Or 2, 2 dimensional x-ray pictures...
 
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If it's a filament bulb (producing significant heat), you could take thermal images of the six faces. The temperature distribution over the faces could give a good indication of the bulb's position.
 
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  1. Finding the box's balance point should reveal the bulb's position; centered, or on one side, or in a corner.
  2. Shaking the box would tell us if the bulb is free to move in the box. If yes, stop shaking. The bulb will be at the lowest point.
  3. If wires stick out of the box, pull them. The bulb should be drawn to the point where the wires penetrate.
  4. Crush the box down to the shape of the bulb.
  5. You put the bulb in. I'll force you to tell me where in the box you put it. Alternatively, I'll watch the video of you putting it in.
  6. I'll guess the position and challenge you to prove me wrong.
Thanks for the OP. This is fun. When you make a challenge like this, locking down the rules is the hardest part. Changing the rules is the most fun part for the challenger.
 
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anorlunda said:
Changing the rules is the most fun part for the challenger.
7. spinning the box to determine center of mass...
 
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8. Cause the bulb to shatter. The pieces will be found at the bottom.
9. If an incandescent bulb, use a DC current and a compass needle to detect magnetic fields.
10. If fluorescent or LED, look for RF interference.
11. If incandescent, use low frequency AC. Listen for the mechanical vibrations at 2x the AC frequency as the filament expands and contracts with instantaneous power.
 
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12. sonar?
That would be adaptable I think... like how a bat could see it, perhaps.
 
anorlunda said:
call it ultrasound
I did at first and changed it... wasn't sure if it works through air...
 
anorlunda said:
having fun finding all the loopholes in his problem statement.
...now I'm having fun wondering if bats can "see" through walls... too! I just googled it and found something about cellphone seeing through walls...
 
What if I want to see the light from the light bulb?
 
16. ask Schrödinger's cat where it is
 
17. If the box is wood or cardboard, bring in termites - they should eat the box letting you see where the bulb is.
18. Let the box corrode, erode chemically, mechanically - you should then see where the bulb is
19. Poke fine rods through the box - obstruction, you are hitting some part of the bulb.
20. Place moths with accurate and precise GPS - record their movement and one can determine where the bulb is.

21 is the challenge

Edit - had to edit the list #
 
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Magnetic resonance 3D imaging. That tells not only where cancerous masses are but their shape/ size and where tiny gold implanted reference spheres (markers for daily localized radiation treatments extending over weeks, to not do too much damage to normal tissue) are.

Modern MRI machines used with accurately shaped beams from linear accelerators. The cross section shape of beam changes with beam approach angle to be same as the cross section area of the target "seen" from the current beam angle.
 
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Make separately large thermal gradients across the box (one for each direction thru box) and with no power applied, measure the resistance between the wires. This assumes lamp is a tungsten filament type. The resistance hot, is almost twice that when cold. (Why those lamps often burn out at first turn on - large initial current surge.)
 
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By using thermal camera shoot the box surface from the top, front and right side could be known the light bulb position. Good luck.
 
If it's a traditional light bulb...simplest solution metal detector. Depending on the size of the box the place you get the loudest tone will be the location... Some will even tell you what metal at what depth.
 
Well, how about a way to extract the light wave emitted by the light bulb? Is that possible
 
fredreload said:
Well, how about a way to extract the light wave emitted by the light bulb? Is that possible

Don't change the question at this late stage. Use your own common sense. You say "extract light" and you say "not transparent". Doesn't that sound like a contradiction? If there was a way, it would by definition be transparent. There is no physics to learn from contradictory language.
 
fredreload said:
Well, how about a way to extract the light wave emitted by the light bulb? Is that possible
I suspect these questions are related to the questions that you've been asking about brain imaging in the biology form.

Anyway, if the bulb is incandescent, you could do thermal imaging (if the box is transparent to IR) to estimate the temperature of the filament inside the bulb. Since the light is produced by a well known physical mechanism, you could then model the spectrum of light output by the bulb based on measured parameters.
 
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