Recent content by DanteBR

Does anyone know if such a thing exist? Imagine that the dynamo is in a vacuum chamber. The rotating magnet does not touch the coil, and there is no air, so there is no aerodynamic drag. So, I wonder if there is something like a "magnetic friction force", decelerating the rotating magnet...

There is a "magnetic friction force" in a dynamo? In a rotating dynamo, where the magnet rotates surrounded by a coil, there is something like a "magnetic friction force"? The magnetic field causes an effect similar to mechanical friction, that can slow down the revolving magnet?

Hummm... I understand... So, I think I'm convinced... I will stop trying to think about a manner to astronauts in a tripulated mission to Mars could communicate instantly with Earth...

Wait a minute! I had another "crazy" idea! If it were built in the outer space a very large bar of 900 thousand kilometers in length, and there was an engine so powerful that it could push one end of the bar, making the whole bar to move some 5 centimeters forward in a single bound ... If I...

Hummm.. So it's really impossible to transmit information faster than speed of light... Thanks a lot!

Cool... So, the "final" steep: Imagine that NASA can make a "mega-giant" eletro-magnet and put it in the outer space... Imagine that the glass wall and the Disc can be put in a spaceship 900 thousand kilometers away from the "mega-giant" eletro-magnet... The 900 thousand kilometers distance...

Nice. I'm very happy to know it should work. Now, my question is: If we could make an eletro-magnet more strong, with a stronger magnetic field (measured in gauss), would it attract the metallic disc from a greater distance? Instead of just 5 meter, it would be possible to place the glass wall...

Hi. First I want to say that I'm not a physicist. I'm just a layman. Well, I'm very disturbed with an experiment that I had imagined and I wish someone would help me understand if my reasoning would be correct... First of all, I wish to know if this experiment could work in a...

When a permanent magnet attracts an iron coin, there are only "virtual photons" involved in this process? If the coin is on a table, and the permanent magnet is positioned a few centimeters above the coin, what about Earth's gravity attracting the coin? Why the virtual photons are "stronger"...