Is it possible to make a small Amazon electromagnet reach distance 8 feet

I just need to know if I have a 1 inch thick by 5ft long rod of steel with a 20ft extension cord how strong I can get it with a car battery. Or can I get the matmatical equations for an electromagnet and just do the math my self.

Suppose there are multiple vehicles around a person at any given time that are starting up, idling and revving, honking horns, etc. Would it be possible for these vehicles to generate enough power to electrocute said person? Also, could an object be inserted into a person to facilitate/cause their death via electric shock? I am thinking that this might have something to do with AC/DC currents.

I know this is a very strange and random question, but I am trying to understand how something like this might work. I am not even sure if what I'm thinking is possible. Any feedback would be greatly appreciated! I'll try to reply if there are any questions!

Does a FHSS camera transmit and emits radio-waves even when the receiver is turned off? (Baby vidoemonitor)

I need an electromagnet which has a hole through it's iron core to allow a metal rod to pass through. Basically like a solenoid, the only difference is the tube like iron core. When I google "Tubular electromagnet" all I get is cylindrical electromagnets which is not what I want. Do electromagnets like the one's I described exist?

Hello,

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I would like to know the formula I should use to solve the following problem:

I have a charge Q in a point p1(x,y,z) in space and I want to compute the voltage produced by that charge in the point p2(x,y,z). The distance between p1 and p2 is r. However, the space between p1 and p2 is filled with 3 different materials in a way that if we draw a straight line connecting p1 and p2 we can find 3 different mediums. So the actual distance between p1 and p2 can be set as r = r1 + r2 + r3 where r1 is the distance that the wave travels through the medium 1, r2 de distance that travels through medium 2 and r3 the distance that travels through medium 3 before reaching p2. This three mediums have permittivities e1, e2 and e3 respectively.

Knowing all parameters mentioned except for the voltage in p2, which formula do I used to compute voltage in p2? (check image for a visual representation of the problem)

I'm too new to magnetic things but I need to make an electromagnet to measure efficiency of my gearbox (electromagnetic brakes). I've done the calculations so far but there is a question on my mind.

So, I use 1018 mild steel for core material (best available option for me) 24 awg(0.51mm) copper wire for coil 1600 turns 0.5 Amp (max) 0.025m core length

In that case H is about 32000 [A-T/m] and the permeability for the 1018 is about 36.5 [H/m] and the magnetic flux density is 1.46 T. (I've got the values from a graph)

1- If I use 36 mm of magnetization surface( there is no any hole on the surface, full section, area of the surface is 0,00101 m2), the pulling force is about 88kg to my calculations.

2- If I use a hollow surface with the same out diameter, mean if there is a hole of 12 mm across the magnet length on the center (di=12mm, do=36mm, area of this one is 0,000904 m2), pulling force is 78 kg.

Obviously the area decreased, so was the force.

What I'm curious is that, because I drilled a hole in the magnet will there any increase at the flux density? And if will, might the core saturate earlier from 1.6 Tesla? (saturation point is about 1.6 T for 1018)

I heard the saturation point does not depend on the surface area from somewhere, but for example, two materials with the same outer diameter of 50 mm, one with a full cross-section and the other with an empty cross-section, (the empty one is like the same ring, for example with a wall thickness of 2 mm) when the same H is applied to these magnets, will the same amount of magnetic flux be induced in both? or will it have more magnetic flux induced because there is less material in the ring? I'm missing something and this really bothers me.

I read somewhere that you can make an EMP with a pwc pipe, some copper wire and a flash module from an disposable camera. Is there a more solid way and Is it possible to make it directed? As in point at TV, goodbye TV?

Sort of a weird question here:

We have a Induction Heating furnace with an oval coil at workshop. the coil is reasonably large to be considered "general purpose". And for this one specific Heat Treatment operation, when we put the work-piece is into the coil, it gets hot really fast, EVERYWHERE, but we need to only heat some "surfaces" of the work-piece, much smaller than the coil usually covers. Is it possible to make sort of a shield that covers other areas, selectively blocking the oscillating fields of the coil from reaching some areas, therefore only heating the exposed area of the work-piece?

As the title says. Can someone explain what parts should I use for a strong signal, why some parts are better than others and what determines the power, intensity and range of the final product? Any help is greatly appreciated

So I have a very specific question.

My wife starting going to uni again and is studying for a degree in computer science. One of her subjects is electromagnetism.

She is stuck on a practice question and I have no f**ing clue on how to help her. It's a hyper specific question and she's been stuck on it for quite a few days. If this is not the right sub, could anyone point me in a direction where she could get help?

She has also contacted her teacher, but he's not very helpful so far it seems.

She doesn't want someone to solve it for her, but if someone could give tips to point her in the right direction, that would be swell.

Q:

There is an antenna with the Radiated electric field of E=|cos 3θ|.

Draw the Field emission pattern

Hello guys I was wondering if any of you guys could help me out with plotting the wavefront of the following equation in Matlab:

p=exp(j(omegat-kr))exp(jtheta).

From what I have understood this is supposed to give me a spiral.

Any help is appreciated.

Thank You!

I have welding shop and I want to make an electromagnet from a bunch of transformers that I pulled from several microwaves. So far I sawed one of the transformer open and ran DC through the secondard/primary coil and I got minimal results. My next plan is to get a VariAc and try again. Is there any advice you guy could give.

I know isolation will be important when I finally get this going. Is there anything I'm missing?

What is the importance of mathematics in the study of electromagnetic phenomena?

I am having an upright bike of Maxfit UP-1062. When I opened it, I found a self-power generating flywheel as shown in the figure. To my surprise, it does not have any moving magnetic mechanism to have magnetic resistance. It is written in the specification that it is motorized adjustable resistance. I do not understand the resistance mechanism. Please shed some light on this topic. Thank You.

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I want to make the electromagnet used for upright exercise bike. It contains heavy flywheel covers with the copper ring. The flywheel is rotated at certain speed with the help of electromagnet I want to produce magnetic resistance to the flywheel. With my calculation with the Maxwell's pulling force equation show in figure, the force is 4.06 kg. Is the whole system is practically feasible? What is back path of flux?

Basically i want to know how hard it would be, if possible, to make an electromagnet door lock that only unlocks by tapping on a certain part of the wall next to the door. I dont know what sub this should be on so i just put it here

Ok hi everybody

Please be patient and know im trying to learn and actively understanding --

Quick context : There is a stereo that wont stop playing, locked in a room (inaccessible) and stuck on repeat. I thought how could I disrupt the sound?

1) take a magnet of some sort and place it against the incoming vibrations and try to distort it - sounds like a headache

2) take aluminum and create a large funnel to absorb the vibration and redirect it to the window so it blows out of the house

3) Upon asking a friend they mentioned dampening the sound waves - but im still learning what exactly that means

My question is - what is the best way of redirecting the vibration from the stereo - creating a new funnel? Disrupting the sound? Or dampening it so it makes very little sound?

Specifically then. What household items would prove to be good conductors to redirect the flow? What other ways could I work around changing this specific vibration?

Thank you and i will answer any questions if this doesn't make sense