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Position yourself on the surface of body A and shoot a ray in any direction. After a certain number of reflections from the mirror surfaces (possibly none) it will hit either body A or body B. Now expand the ray into a very narrow cone, such that all the rays in the cone finish on the same body. Looking into that cone you will see a radiant intensity ...


Ingenious. A and B are small, but they cannot be points.The image of B is magnified at A. Therefore if A and B are the same size, some of the light from B will miss A.


There is a confusion between the terminology "perpetual" , which means "continuously", devices that almost move forever, and a machine that can produce energy. As the other answers point out energy is conserved and if it looks as if energy is provided from nothing a closer analysis shows the mistake, as in the drinking bird perpetual setup. In the case of ...


You might be able to get it to work for quite a while, depending on your skill as an engineer. But there is a critical difference between a well-engineered machine that runs for a while, and a perpetual motion machine that runs forever without input. The latter is impossible.


The key here is the antimagnetic strip, quite aside from whether or not such a device can be built. When you insert the anti-magnetic strip, you must change the shape of the magnetic field. You must force the magnetic field to "leave" the high permeability ball. The same magnetic induction $|\vec{B}|$ in a high permeability $\mu$ material represents a lower ...


If the magnet is strong enough to pull the ball up the bottom slope, it will be too strong to let the ball fall. Even worse, as you have drawn the diagram the magnet is pulling the ball down the lower slope when it is toward the left end. Anywhere to the left of where the perpendicular from the magnet to the ramp, the magnet is pulling more right than up. ...


Too many abrupt changes in direction. Also, is this spring powered? If so, I would think it to be simpler by using an electromagnet to apply and cut voltage. More moving parts mean more opportunities of failure.


Newton's first law does not apply to objects, but to observers. If you are an inertial observer, then you will see everything that is not acted upon by a force travelling in a straight line. There's no qualifier on the everything here - if it is not travelling in a straight line, it has a force acting upon it. Non-Newtonian fluids derive their name almost ...

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