Electromaget produces light...

[gmphadte]

"In place of a bulb, an electromagnet produces light; in place of a battery, a capacitor stores the power,"

I read this at the site

anybody explain please?

Gajanan Phadte

 

[UrSv]

What's there to explain? The thing uses an LED as a light source instead of a bulb and there is no battery but a capacitor which is charged by a moving magnet which induces a voltage in a coil when you shake the flashlight.

 

[gmphadte]

In place of a bulb, an electromagnet produces light

If I am not wrong, I think there is no LED either

Gajanan Phadte

 

[Elso Kwak]

Re: Electromaget produces light.../IQ

"In place of a bulb, an electromagnet produces light; in place of a battery, a capacitor stores the power,"

I read this at the site

anybody explain please?

Gajanan Phadte

Hi,
I did the IQ test on that site and answered all questions at random. Guess what my IQ was rated 91........
Do I need to say more?

Edit quote from the site:

Your IQ score is 91
This number is based on a scientific formula that compares how many questions you answered correctly on the Classic IQ Test relative to others.
Your Intellectual Type is Precision Processor. This means you're exceptionally good at discovering quick solutions to problems, especially ones that involve math or logic. You're also resourceful and able to think on your feet. And that's just some of what we know about you from your test results.

I feel so flattered. Also the suggestion to start a study at the university is enlighting as I already have an academic degree.

 

[blu_line]

There is a Led

I have seen and played with such a torch light.
There is a Led inside.

UrSV is right on how the energy is produced ans stored.

grtz

Simon

 

[gmphadte]

Transfered epithet (something like that) at wrong place at that site

Funny english
t o becomes...
g o becomes...

Rest all is piece of cake
Thanks all

Gajanan Phadte

 

[muhy3]

Simply put this little torch uses a wire-wound coil and a fairly strong magnet, similarly to a solenoid only instead of charging the coil with another current source, the in/out motion of the magnet through the center of the coil induces a current which is then transmitted to a capacitor. Then this energy is used to light a low power led.

There is no way a magnet could produce light and it is somewhat misleading to the unknowing for the company to say that the "bulb" has been replaced by the electromagnet. That's kinda like saying "we replaced the batter with a light", really absurd.

 

[Prune]

Let's see now...
Google search: NightStar
Second result: http://www.nightstar1.com/
Second sentence: Once charged, NightStar provides light for up to 20 minutes from the LED.

 

[UrSv]

If I am not wrong, I think there is no LED either

Gajanan Phadte

As stated by the others and looking at the pictures from the "more info" link on that site I think there is little doubt that there is indeed an LED:

An externally hosted image should be here but it was not working when we last tested it.

 

[Sch3mat1c]

There is no way a magnet could produce light

Not strictly true, since light is an electromagnetic wave it stands to reason that spinning a magnet would produce alternating north and south fields, and since a moving magnetic field produces a moving electric field and vice-versa, you immediately have the EM field. This would produce a horizontal pattern of exactly one frequency, but unfortunately, it is notoriously difficult to spin anything at 24P RPM (that's peta-, 10^15, one k up from tera). (For why this happens, imagine the magnetic field produced by the magnet, then imagine it being twisted as it rotates. It 'expands' out from the magnet with light speed, so it has to be spun *very* fast to get such narrow wavelengths.)

Tim

 

[muhy3]

You said it yourself Sch3matic, a magnet would need to be spun at 24P RPM which from what I figure is preety much useless because at that speed the material would break up and any magnetic field will actually break apart/away from the magnet, kind of like bashing a magnet with a hammer, it will loose its magnetism, thats why electromagnets are used to control electron beams, and not used to produce light.

 

[Prune]

There is no material that can spin that fast without breaking apart. Even a neutron star can't do it, despite the enormous gravity (not to mention that near the surface velocity would exceed the speed of light by many orders of magnitude, which is clearly ludicrous). So no, a magnet cannot directly produce light.

 

[Prune]

I should qualify my statement as that it cannot produce light directly by means of its magnetism (as opposed to, say, its thermal black body radiation).

 

[Sch3mat1c]

Well no, but you could use a magnet spun at a more non-relativistic rate to generate radio frequency photons.

Oh - there ARE things which can move at that speed - electrons! Visible light photons are small enough that they can only cover a few molecules if you're lucky, so it's very easy for electrons to be individually manipulated.

Tim

 

[Nasse]

Hobbyists have done such energy storing lamps using a stepper motor as a generator. I saw one circuit there was just stepper motor, bridge rectifier, electrolytic cap, series resistor and superbright led

I think that torch under discussion was cheaper to construct without special generator, just a magnet or iron piece inside a plastic tube and coil wound around

But good idea, no batteries that go flat sooner or later. Or in cold weather when batteries freeze