user273872
  • Member for 6 years, 7 months
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Would a DC motor not work if using a bare copper wire?
2 votes

Yeah it requires insulation. I was confused about this too a long time ago, because all the motors I tore apart looked like they had bare copper wire windings, yet it makes sense that the current ...

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The physics of tripping on a stone
2 votes

If you think of the runner as being stationary and the ground as being the thing that moved, you can think of a rock hitting a rigid object off center. A torque is imposed on the body based on the ...

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Strongest Magnet Material - Theoretical Limits?
1 votes

Check out the answer to this related question: How to wire a STRONG electromagnet? Note that the saturation of an electromagnetic core is happening because the external field can't do any more to line ...

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Can pressure be negative?
1 votes

Your sources were probably trying to keep you from getting confused when they threw in a minus sign later. Typically you deal with a positive scalar pressure which doesn't have a direction. But like ...

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Gravitational acceleration
1 votes

Newton devised a very good law of gravity (until Einstein came along) where the force between the two bodies is scaled by a very small number usually written as a capital G. It's a general law that ...

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Photon field interaction
1 votes

"is there interaction between photon and electric or magnetic field" With an everyday magnet not so much. With the strongest magnet in the universe, comprised of a super dense substance such as a ...

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Should a Step Up transformer necessarily need more Windings?
0 votes

It looks like you set up your own problem, and you're confused that changing the resistors to arbitrary values (or number of windings), might violate power conservation. Are you sure Pin = Pout in ...

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How is energy conserved in a theoretical circuit where you put a lightbulb and two rechargeable batteries like... (diagram included)
0 votes

I'm not exactly sure on the details, but on a higher level the answer will have to do with conversion of energy. As the first battery is discharging, chemical energy converts to an electromotive ...

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Laser Cutter Power/Wavelength to Cut Paper
0 votes

Aside from the "it's complicated answer," there's also the "check for prior experimental research" answer. Without digging into it very far I used one trick. I found this Wikipedia article on Laser ...

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Help figure out the planet M
Accepted answer
0 votes

1: Mass of the planet and mass of the star determines the distance and then it's just a geometry problem, draw a triangle between the star and the moon and a point on the planet, think about eclipses. ...

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Magnetic flux and flow of electrons
0 votes

All magnetic flux stems from movement of electric charge, so it makes sense that it can stimulate movement of electric charge. A permanent magnet has a certain magnetic field around it that is the ...

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Capacitance when one plate has more surface area
0 votes

I found an answer: Blockquote For asymmetric capacitors, the total capacitance can be taken as that of the electrode with the smaller capacitance (if C1 >> C2, then Ctotal ≈ C2). https://en....

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What would happen on the earth if we placed a huge mirror (focusing all sunrays in one point on earth) in space?
-1 votes

I recently took a lense with a diameter over a meter long and focused the sun light onto a piece of metal (pop can) which promptly began to vaporize. The earth has a diameter on the order of tens of ...

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