1
vote
0answers
50 views

What are the implications of running a motor well above its rated frequency?

Plenty of material on the web will tell you what to expect when you run a 50/60Hz 3-phase induction motor at 60-80Hz, but what if you would like to run it at 140Hz? or 250Hz? Or at any frequency? ...
0
votes
1answer
184 views

Force of electromagnet on piece of iron

I can find equations to give the force of an electromagnet on a piece of iron when the iron touches the electromagnet. But what about when the iron is some distance from the electromagnet? ...
5
votes
1answer
299 views

Can an induction coil heat two layers of metal?

Imagine we have an induction coil which is strong enough to heat a sheet of metal. We can put a sheet of ferromagnetic metal close to the coil at distance $h_1$, and it gets heated to temperature ...
-1
votes
2answers
99 views

What could be some applications for a highly compressed magnetic field?

If you had a powerful electromagnet in the shape of a hollow sphere in which the top and bottom halves are the opposing poles, what can the magnetic filed at the center of the sphere be used for?
0
votes
4answers
2k views

Magnetic flying engine

I invented a flying engine moving entirely by magnetic forces (such as the force related with magnetic field of the Earth). See http://porton.wordpress.com/2011/12/23/magnetic-vehicle/ The question ...
2
votes
2answers
1k views

Do multiple permanent magnets aggregated together approach the same strength as a single magnet of the same size?

Here's an applied physics question. ;) If I buy some cube or sphere magnets like these, can I aggregate them together to create a stronger magnet (almost as strong as a single magnet)?