How do you determine the polarity of an electromagnet?
Q. How do you design an electromagnet to have it's poles face a determined direction? Thanks for the help :)
Asked by Mike - Wed Jul 15 19:33:03 2009 - - 1 Answers - 0 Comments
A. Google "right hand rule magnetism." Or you could use a compass.
Answered by LeAnne - Wed Jul 15 19:44:19 2009
Q. How do you design an electromagnet to have it's poles face a determined direction? Thanks for the help :)
Asked by Mike - Wed Jul 15 19:33:03 2009 - - 1 Answers - 0 Comments
A. Google "right hand rule magnetism." Or you could use a compass.
Answered by LeAnne - Wed Jul 15 19:44:19 2009
How can I use a transistor to turn an electromagnet on and off?
Q. I tried connecting the transistor to a 10V battery and then to my electromagnet but it got blown up in two... I also tried putting a resistor in series but the electromagnet wouldn't even work! Is the resistor taking away all the power? I need to use my PC to control the electromagnet, any help?
Asked by UofT guy - Sat Jan 20 13:41:10 2007 - - 4 Answers - 0 Comments
A. There are several things to consider. 1. How much current do you need to pass through your electromagnet coil? This will help you determine what Resistor value you will need. The coil itself will probably have a low resistance. You can measure this with an ohm-meter. A resistor in series with the coil will dissopate most of the power if the resistor is larger than the coil resistance. This is alright, but you need to make sure the resistor can handle the power. P = I^2*R. 2. What kind of transistor are you using? If you are using a BJT (NPN or PNP) you will need to supply a current to the base of the transistor to turn it on. You will also need a resistor in series with the base to prevent the B-E junction of the transistor… [cont.]
Answered by Jess - Sat Jan 20 15:03:39 2007
Q. I tried connecting the transistor to a 10V battery and then to my electromagnet but it got blown up in two... I also tried putting a resistor in series but the electromagnet wouldn't even work! Is the resistor taking away all the power? I need to use my PC to control the electromagnet, any help?
Asked by UofT guy - Sat Jan 20 13:41:10 2007 - - 4 Answers - 0 Comments
A. There are several things to consider. 1. How much current do you need to pass through your electromagnet coil? This will help you determine what Resistor value you will need. The coil itself will probably have a low resistance. You can measure this with an ohm-meter. A resistor in series with the coil will dissopate most of the power if the resistor is larger than the coil resistance. This is alright, but you need to make sure the resistor can handle the power. P = I^2*R. 2. What kind of transistor are you using? If you are using a BJT (NPN or PNP) you will need to supply a current to the base of the transistor to turn it on. You will also need a resistor in series with the base to prevent the B-E junction of the transistor… [cont.]
Answered by Jess - Sat Jan 20 15:03:39 2007
Using an electromagnet and an iron weight, how can the electromagnet be used to raise the barrier?
Q. I really need help on this... Using an electromagnet and an iron weight, how can the electromagnet be used to raise the barrier?
Asked by Demi - Tue Jan 6 12:41:19 2009 - - 3 Answers - 0 Comments
A. 1. Hinge the barrier. Arrange the iron weight to balance most of the weight of the barrier. As part of the weight, include an iron rod, hinged to the weight end of the barrier. 2. Put a solenoid coil around the bottom of the rod, and energise it. The rod will be pulled by the magnetic field, raising the barrier. The rod would need to be guided to remain central in the coil. Half its length would need to be enough to raise the gate to the required height. It would also need adjustment (possibly) so the weight of the barrier is able to lower it when the coil is de- energised.
Answered by Technobuff - Tue Jan 6 20:16:05 2009
Q. I really need help on this... Using an electromagnet and an iron weight, how can the electromagnet be used to raise the barrier?
Asked by Demi - Tue Jan 6 12:41:19 2009 - - 3 Answers - 0 Comments
A. 1. Hinge the barrier. Arrange the iron weight to balance most of the weight of the barrier. As part of the weight, include an iron rod, hinged to the weight end of the barrier. 2. Put a solenoid coil around the bottom of the rod, and energise it. The rod will be pulled by the magnetic field, raising the barrier. The rod would need to be guided to remain central in the coil. Half its length would need to be enough to raise the gate to the required height. It would also need adjustment (possibly) so the weight of the barrier is able to lower it when the coil is de- energised.
Answered by Technobuff - Tue Jan 6 20:16:05 2009
How could I build a pulsing electromagnet that could generate a 2tesla magnetic field?
Q. I would like to construct a figure eight style electromagnet with a coil of about 2 centimeters diameter on either side and need it to generate a 2T field once per second. What kind of power source would I need to do this?
Asked by Theava - Mon Dec 24 17:44:09 2007 - - 2 Answers - 0 Comments
A. A big one. You have not supplied sufficient information to answer your question. * how wide is the gap * what is the cross-sectional area of the 2T field? * what does the field need to decay to between electrical pulses? In addition, 2T is awfully close to the saturation limit for pure iron, so your material selection will be critical. Why a figure 8 electro-magnet? What you are trying to build sounds a great deal like a magnetizer for permanent magnets, or a rail gun. One power system that could do this job consists of several capacitor banks, each charged from a separate high voltage, high current DC supply, in turn each is switched to the coil(s) to generate the large pulse.
Answered by Nigel M - Mon Dec 24 18:58:06 2007
Q. I would like to construct a figure eight style electromagnet with a coil of about 2 centimeters diameter on either side and need it to generate a 2T field once per second. What kind of power source would I need to do this?
Asked by Theava - Mon Dec 24 17:44:09 2007 - - 2 Answers - 0 Comments
A. A big one. You have not supplied sufficient information to answer your question. * how wide is the gap * what is the cross-sectional area of the 2T field? * what does the field need to decay to between electrical pulses? In addition, 2T is awfully close to the saturation limit for pure iron, so your material selection will be critical. Why a figure 8 electro-magnet? What you are trying to build sounds a great deal like a magnetizer for permanent magnets, or a rail gun. One power system that could do this job consists of several capacitor banks, each charged from a separate high voltage, high current DC supply, in turn each is switched to the coil(s) to generate the large pulse.
Answered by Nigel M - Mon Dec 24 18:58:06 2007
How do I build an electromagnet that can lift 500 grams?
Q. For Physics class, I have to construct an electromagnet that cannot exceed the length of 30 centimeters(1 foot), but can lift 500 grams of paperclips (equivalent mass of a stapler). The only power source I can use is a single D-Cell battery and insulated wires. I have to connect the wires to the battery and then wrap the wires around an iron nail. But is there a more effective way to magnetize this amount of weight using these materials? Any help or suggestions would be great.
Asked by Natalie Scottsworth - Mon Apr 14 18:37:02 2008 - - 1 Answers - 0 Comments
A. It's current, not voltage, that makes the emf around the nail. So, I'd suggest using the smallest diameter wire you can, and compacting it as much as possable by using the thinest insulation you can get away with...like maybe that wire that has a coating of varnish-like material on it instead of plastic insulation. Use a fresh battery...even though it's current you want, it's voltage that provides the push to make the current. Use the shortest amount of wire possable, since the more wire, the more resistance, and the lower the current. Basically, I'd just take some wire , wrap it around a nail, hold the ends to a battery and see what happens. Good luck, and have fun experimenting!
Answered by BeachBum - Mon Apr 14 19:04:22 2008
Q. For Physics class, I have to construct an electromagnet that cannot exceed the length of 30 centimeters(1 foot), but can lift 500 grams of paperclips (equivalent mass of a stapler). The only power source I can use is a single D-Cell battery and insulated wires. I have to connect the wires to the battery and then wrap the wires around an iron nail. But is there a more effective way to magnetize this amount of weight using these materials? Any help or suggestions would be great.
Asked by Natalie Scottsworth - Mon Apr 14 18:37:02 2008 - - 1 Answers - 0 Comments
A. It's current, not voltage, that makes the emf around the nail. So, I'd suggest using the smallest diameter wire you can, and compacting it as much as possable by using the thinest insulation you can get away with...like maybe that wire that has a coating of varnish-like material on it instead of plastic insulation. Use a fresh battery...even though it's current you want, it's voltage that provides the push to make the current. Use the shortest amount of wire possable, since the more wire, the more resistance, and the lower the current. Basically, I'd just take some wire , wrap it around a nail, hold the ends to a battery and see what happens. Good luck, and have fun experimenting!
Answered by BeachBum - Mon Apr 14 19:04:22 2008
How does the size and length of the core affect the magnetisation of an electromagnet?
Q. Specifically, i'm trying to build an electromagnet that features a solenoid which may only cover less than half the distance of the core, so that the core is protruding from the end of the solenoid. By turning on the electromagnet, will the entire core still magnetise or only the part covered by the solenoid? Furthermore, how does the diameter of the core and length of the core outside of the solenoid affect the overall strength of the magnetism? And, apart from soft iron (which is impossible to obtain these days, believe it or not), are there any really good materials i can use for the core? Mild steel was a suggestion. Thanks!
Asked by crimsonxero - Wed Mar 21 03:02:18 2007 - - 4 Answers - 0 Comments
A. The core will be magnetised uniformly throughout its length. The strength of the magnet is determined by the number of turns of wire going round the solenoid and the current passing through the circuit. Ampere- turns. However the cross sectional area of the solenoid also has an effect . It is similar to a conductor carrying current. i.e. the larger the c.s.a.the more flux can flow and of course the stronger the magnet. The longer the solenoid the weaker the magnet. You can get soft iron from a large construction site. Rather than using a large c.s.a . I suggest you use thin iron tying wire. and and build up your solenoid from several lengths and bind them together..
Answered by mad_jim - Wed Mar 21 20:04:29 2007
Q. Specifically, i'm trying to build an electromagnet that features a solenoid which may only cover less than half the distance of the core, so that the core is protruding from the end of the solenoid. By turning on the electromagnet, will the entire core still magnetise or only the part covered by the solenoid? Furthermore, how does the diameter of the core and length of the core outside of the solenoid affect the overall strength of the magnetism? And, apart from soft iron (which is impossible to obtain these days, believe it or not), are there any really good materials i can use for the core? Mild steel was a suggestion. Thanks!
Asked by crimsonxero - Wed Mar 21 03:02:18 2007 - - 4 Answers - 0 Comments
A. The core will be magnetised uniformly throughout its length. The strength of the magnet is determined by the number of turns of wire going round the solenoid and the current passing through the circuit. Ampere- turns. However the cross sectional area of the solenoid also has an effect . It is similar to a conductor carrying current. i.e. the larger the c.s.a.the more flux can flow and of course the stronger the magnet. The longer the solenoid the weaker the magnet. You can get soft iron from a large construction site. Rather than using a large c.s.a . I suggest you use thin iron tying wire. and and build up your solenoid from several lengths and bind them together..
Answered by mad_jim - Wed Mar 21 20:04:29 2007
will a powerful electromagnet affect the electronics on a remote control car?
Q. I have a 1/6 scale dune buggy and i would like to mount it in the back of my 4x4 so i can remove it with the flick of a switch.I would like to use an electromagnet but i dont want to damage the electronics in the RC car.Help!
Asked by isaacchef - Mon Sep 24 01:58:14 2007 - - 2 Answers - 0 Comments
A. The magnetic field will not harm the electronics, but turning the electromagnet on and off will generate high voltage spikes and an EM field which may cause problems. When you make your electromagnet, be sure and put a damper diode in parallel with the coil AND an RC snubber network (you can Google "damper diode", and "RC snubber network" to get examples). .
Answered by tlbs101 - Thu Sep 27 17:37:01 2007
Q. I have a 1/6 scale dune buggy and i would like to mount it in the back of my 4x4 so i can remove it with the flick of a switch.I would like to use an electromagnet but i dont want to damage the electronics in the RC car.Help!
Asked by isaacchef - Mon Sep 24 01:58:14 2007 - - 2 Answers - 0 Comments
A. The magnetic field will not harm the electronics, but turning the electromagnet on and off will generate high voltage spikes and an EM field which may cause problems. When you make your electromagnet, be sure and put a damper diode in parallel with the coil AND an RC snubber network (you can Google "damper diode", and "RC snubber network" to get examples). .
Answered by tlbs101 - Thu Sep 27 17:37:01 2007
How do I determine the north and south pole in an electromagnet?
Q. I am making a locking device where a neo magnet will hold a lid down tightly by sticking itself to a piece of steel. I want to make that piece steel an electromagnet so that when it turns on it will repel the neo magnet enough so I can open the lid. But to do that I need to be able to determine the poles on the electromagnet and keep it constant every time I run a current through the coil.
Asked by Mike - Tue May 19 03:20:58 2009 - - 2 Answers - 0 Comments
A. It takes a common everyday compass. The S pole of the needle in a compass points to the N magnetic pole of the Earth. Bring the compass NEAR the magnet in question and the needle end which points to the N magnetic pole will point toward the N pole of the magnet in question. The same apples to your electromagnet. Energize the coil (DC only. AC will cause a fluctuation, reversing field, in sync with the power line which changes direction 60 times per second.) and then bring the compass NEAR and the needle end which points to the N magnetic pole will point to the end of the coil which is the N pole of the electromagnet. Then, all you need do is position the electromagnet coil correctly according to the determination of which pole is which.… [cont.]
Answered by NickyD - Thu May 21 12:57:24 2009
Q. I am making a locking device where a neo magnet will hold a lid down tightly by sticking itself to a piece of steel. I want to make that piece steel an electromagnet so that when it turns on it will repel the neo magnet enough so I can open the lid. But to do that I need to be able to determine the poles on the electromagnet and keep it constant every time I run a current through the coil.
Asked by Mike - Tue May 19 03:20:58 2009 - - 2 Answers - 0 Comments
A. It takes a common everyday compass. The S pole of the needle in a compass points to the N magnetic pole of the Earth. Bring the compass NEAR the magnet in question and the needle end which points to the N magnetic pole will point toward the N pole of the magnet in question. The same apples to your electromagnet. Energize the coil (DC only. AC will cause a fluctuation, reversing field, in sync with the power line which changes direction 60 times per second.) and then bring the compass NEAR and the needle end which points to the N magnetic pole will point to the end of the coil which is the N pole of the electromagnet. Then, all you need do is position the electromagnet coil correctly according to the determination of which pole is which.… [cont.]
Answered by NickyD - Thu May 21 12:57:24 2009
If you increase the current in a electromagnet will the time it takes for the m. field to spread out decrease?
Q. Looking at the relation current is directly proportional to change in magnetic flux over change in time. If you decrease the time the current produced will proportionally increase but let say a generator works with a electromagnet to produce a change in flux to increase the EMF produced. If you increase the current in the electromagnet will the change in time decrease and a larger EMF be produced?
Asked by Wynand N - Wed Apr 2 18:33:12 2008 - - 1 Answers - 0 Comments
A. Ok, here you are getting confused over the term d /dt, which is the change in magnetic flux over change in time. What you have said is true only if the change in magnetic flux remains the same when the change in time decreases. However, this is usually NOT true, because the rate of change in magnetic flux is usally constant, as it is usually in the case of a electric generator. So let me re-iterate: if the amount of change in magnetic flux is the same when the amount of time decreases, then YES, the current in increases and thus the EMF produced also increases. But if the amount of change in magnetic flux decreases when you decreases the amount of time, then obviously there'll be NO change in current or EMF.
Answered by PhysicsDude - Sun Apr 6 15:16:22 2008
Q. Looking at the relation current is directly proportional to change in magnetic flux over change in time. If you decrease the time the current produced will proportionally increase but let say a generator works with a electromagnet to produce a change in flux to increase the EMF produced. If you increase the current in the electromagnet will the change in time decrease and a larger EMF be produced?
Asked by Wynand N - Wed Apr 2 18:33:12 2008 - - 1 Answers - 0 Comments
A. Ok, here you are getting confused over the term d /dt, which is the change in magnetic flux over change in time. What you have said is true only if the change in magnetic flux remains the same when the change in time decreases. However, this is usually NOT true, because the rate of change in magnetic flux is usally constant, as it is usually in the case of a electric generator. So let me re-iterate: if the amount of change in magnetic flux is the same when the amount of time decreases, then YES, the current in increases and thus the EMF produced also increases. But if the amount of change in magnetic flux decreases when you decreases the amount of time, then obviously there'll be NO change in current or EMF.
Answered by PhysicsDude - Sun Apr 6 15:16:22 2008
What happens when one tries to make an electromagnet with a magnetic core?
Q. I know that they say to use an iron core when making an electromagnet because iron doesn't form a permanent magnet. But, when would happen if wire with flowing electricity where to be placed next to or around an already permanent magnet (made of ceramic). I need this for a science project. Thanks!
Asked by megamak93 - Wed Nov 14 19:10:59 2007 - - 3 Answers - 0 Comments
A. If freely suspended (for example by fishing wire or string), changing the current thru a wire near a magnet will apply various forces on the wire. The force on a charged particle due to a fixed magnetic field is equal to the charge (q) times the velocity vector (v) crossed with the magnetic field (B) F = q*v x B Because current thru a wire is effectively a positive charge flow at constant velocity, a fixed magnetic field will create a force on the wire. The units of q*v are Coulombs*meters/second. A wire, however, will instead have a current (amperes) and a length (meters). 1 ampere is simply 1 coulomb per second, so q*v can be replaced with I*L, where I is the current thru the wire, and L is the length of the wire. F=I*L x B A circular… [cont.]
Answered by MooseBoys - Wed Nov 14 19:23:29 2007
Q. I know that they say to use an iron core when making an electromagnet because iron doesn't form a permanent magnet. But, when would happen if wire with flowing electricity where to be placed next to or around an already permanent magnet (made of ceramic). I need this for a science project. Thanks!
Asked by megamak93 - Wed Nov 14 19:10:59 2007 - - 3 Answers - 0 Comments
A. If freely suspended (for example by fishing wire or string), changing the current thru a wire near a magnet will apply various forces on the wire. The force on a charged particle due to a fixed magnetic field is equal to the charge (q) times the velocity vector (v) crossed with the magnetic field (B) F = q*v x B Because current thru a wire is effectively a positive charge flow at constant velocity, a fixed magnetic field will create a force on the wire. The units of q*v are Coulombs*meters/second. A wire, however, will instead have a current (amperes) and a length (meters). 1 ampere is simply 1 coulomb per second, so q*v can be replaced with I*L, where I is the current thru the wire, and L is the length of the wire. F=I*L x B A circular… [cont.]
Answered by MooseBoys - Wed Nov 14 19:23:29 2007
How can you make an electromagnet stronger?
Q. Our Science homework is to find out how to make an electromagnet stronger, i've looked on search engines but i havn't found any answers I really need some help Best answers get extra points lol!
Asked by sae sae - Fri Oct 19 15:14:54 2007 - - 8 Answers - 0 Comments
A. Bigger is better. For any particular geometry, the magnetic power of a copper-wound electromagnet is proportional to the square root of the electrical power dissipated in it. You can choose to use lots of turns of fine wire, with a high applied voltage and low current, or a few turns of heavy wire, with a low voltage but high current. So, you choose your wire size based on the power available and how much of it you wish to use. The other thing you can play with is the geometry. Adequate iron to carry the magnetic field to the workpiece will be helpful.
Answered by rhsaunders - Fri Oct 19 15:26:46 2007
Q. Our Science homework is to find out how to make an electromagnet stronger, i've looked on search engines but i havn't found any answers I really need some help Best answers get extra points lol!
Asked by sae sae - Fri Oct 19 15:14:54 2007 - - 8 Answers - 0 Comments
A. Bigger is better. For any particular geometry, the magnetic power of a copper-wound electromagnet is proportional to the square root of the electrical power dissipated in it. You can choose to use lots of turns of fine wire, with a high applied voltage and low current, or a few turns of heavy wire, with a low voltage but high current. So, you choose your wire size based on the power available and how much of it you wish to use. The other thing you can play with is the geometry. Adequate iron to carry the magnetic field to the workpiece will be helpful.
Answered by rhsaunders - Fri Oct 19 15:26:46 2007
I have to make an electromagnet in my lab. What methods can be used to measure magnet's strength. ?
Q. I have some ideas such as changing the coil length, fiddling with the number of turns on the coil, etc.(tell me more if you know) will affect the strength of the electromagnet. But the main question which arises is, How, How do I measure the strength of the magnet using the common lab equipments. Thanking you in anticipation.
Asked by Hjoss Sampras - Tue Oct 21 11:51:37 2008 - - 1 Answers - 0 Comments
A. If you only need to compare 2 magnets (to decide which is stronger) you can use a big pile of paper-clips. See how many the magnet can pick up at one time (you could also use nails, or any other ferrous item.). Repeat the experiment several times and average the results. You could also have the magnet hold up a tray, and add weights to the tray one at a time until it falls off. Or have the magnet hold up a "fish scale", and add weights to it until it falls, or slowly pull it off, watching the scale so you know where it "pops off". This would also give you an approximate "pounds of pull" measurement. If you need an absolute measure of the magnet's field strength, you could build a detector using a Hall-effect sensor, but that's a lot… [cont.]
Answered by mark p - Tue Oct 21 12:12:39 2008
Q. I have some ideas such as changing the coil length, fiddling with the number of turns on the coil, etc.(tell me more if you know) will affect the strength of the electromagnet. But the main question which arises is, How, How do I measure the strength of the magnet using the common lab equipments. Thanking you in anticipation.
Asked by Hjoss Sampras - Tue Oct 21 11:51:37 2008 - - 1 Answers - 0 Comments
A. If you only need to compare 2 magnets (to decide which is stronger) you can use a big pile of paper-clips. See how many the magnet can pick up at one time (you could also use nails, or any other ferrous item.). Repeat the experiment several times and average the results. You could also have the magnet hold up a tray, and add weights to the tray one at a time until it falls off. Or have the magnet hold up a "fish scale", and add weights to it until it falls, or slowly pull it off, watching the scale so you know where it "pops off". This would also give you an approximate "pounds of pull" measurement. If you need an absolute measure of the magnet's field strength, you could build a detector using a Hall-effect sensor, but that's a lot… [cont.]
Answered by mark p - Tue Oct 21 12:12:39 2008
What is the formula for determining the magnetic field strength of an electromagnet?
Q. I'm guessing current, length of electromagnet, number of turns, or turn density, type of core (mu value?), etc. I'm looking for an exact formula, thx. B=(miu)NI/L What do all the letters stand for? I know some but not all
Asked by liebonton - Sat Apr 26 14:39:33 2008 - - 1 Answers - 0 Comments
A. B=(miu)NI/L
Answered by Rothenstein B - Sat Apr 26 14:43:16 2008
Q. I'm guessing current, length of electromagnet, number of turns, or turn density, type of core (mu value?), etc. I'm looking for an exact formula, thx. B=(miu)NI/L What do all the letters stand for? I know some but not all
Asked by liebonton - Sat Apr 26 14:39:33 2008 - - 1 Answers - 0 Comments
A. B=(miu)NI/L
Answered by Rothenstein B - Sat Apr 26 14:43:16 2008
Why does a loudspeaker have a permenant magnet as well as an electromagnet?
Q. This is homework, so they give a hint which is ... Think about a loudspeaker with just an electromagnet and a piece of iron attached to the paper cone - could it make the cone go backwards and forwards?
Asked by bubba_boo - Tue Jan 20 13:09:31 2009 - - 2 Answers - 0 Comments
A. First, you know that to get movement, you have to have a way of supplying energy. The speaker creates vibrating waves in the air (sound waves) and this takes energy. And the energy has to come from somewhere. Magnets provide a force, but not a source of energy per se. Secondly, you have to have a way to vary the force. If you had two magnets, they could pull the speaker cone one way or the other, But how could they pull each other back and forth, and even back and forth at specific times? they could only do that if you kept moving one magnet or the other, and that would nt be a very effective loud-speaker - with you having to stand there moving it constantly. So having a coil to create a magnetic field gives you two things: a way to… [cont.]
Answered by Midatlantian - Tue Jan 20 14:02:48 2009
Q. This is homework, so they give a hint which is ... Think about a loudspeaker with just an electromagnet and a piece of iron attached to the paper cone - could it make the cone go backwards and forwards?
Asked by bubba_boo - Tue Jan 20 13:09:31 2009 - - 2 Answers - 0 Comments
A. First, you know that to get movement, you have to have a way of supplying energy. The speaker creates vibrating waves in the air (sound waves) and this takes energy. And the energy has to come from somewhere. Magnets provide a force, but not a source of energy per se. Secondly, you have to have a way to vary the force. If you had two magnets, they could pull the speaker cone one way or the other, But how could they pull each other back and forth, and even back and forth at specific times? they could only do that if you kept moving one magnet or the other, and that would nt be a very effective loud-speaker - with you having to stand there moving it constantly. So having a coil to create a magnetic field gives you two things: a way to… [cont.]
Answered by Midatlantian - Tue Jan 20 14:02:48 2009
How do I make an electromagnet with the greatest efficiency??
Q. I want to make an electromagnet with the greatest efficiency. That means making an electromagnet with the LEAST amount of CURRENT that can life the greatest # of paper clips?
Asked by star - Fri Apr 13 03:02:23 2007 - - 1 Answers - 0 Comments
A. Use a small pole with a LOT of uniform windings of a small gauge wire with a very thin insulation.
Answered by waker_me - Sat Apr 14 03:59:31 2007
Q. I want to make an electromagnet with the greatest efficiency. That means making an electromagnet with the LEAST amount of CURRENT that can life the greatest # of paper clips?
Asked by star - Fri Apr 13 03:02:23 2007 - - 1 Answers - 0 Comments
A. Use a small pole with a LOT of uniform windings of a small gauge wire with a very thin insulation.
Answered by waker_me - Sat Apr 14 03:59:31 2007
Can you make an electromagnet with a steel core?
Q. I need to make an electromagnet but soft iron rod seems pretty rare. I have steel rod in abundance, so I was just wondering if this would work instead?
Asked by hoarp001 - Fri Jul 13 20:44:20 2007 - - 6 Answers - 0 Comments
A. That depends on the kind of steel. Stainless steel doesn't work worth beans as a magnetic core, but mild steel should work reasonably well. You must also consider whether the magnet is to run on DC or AC power. If the magnet is to run on AC, and the application is critical, you have some additional things to consider, such as eddy currents, hysteresis losses, and the additional inductive impedance of your magnet.
Answered by devilsadvocate1728 - Fri Jul 13 21:00:51 2007
Q. I need to make an electromagnet but soft iron rod seems pretty rare. I have steel rod in abundance, so I was just wondering if this would work instead?
Asked by hoarp001 - Fri Jul 13 20:44:20 2007 - - 6 Answers - 0 Comments
A. That depends on the kind of steel. Stainless steel doesn't work worth beans as a magnetic core, but mild steel should work reasonably well. You must also consider whether the magnet is to run on DC or AC power. If the magnet is to run on AC, and the application is critical, you have some additional things to consider, such as eddy currents, hysteresis losses, and the additional inductive impedance of your magnet.
Answered by devilsadvocate1728 - Fri Jul 13 21:00:51 2007
what is the advantage of having a ferromagnetic core in an electromagnet?
Q. i know that once the current flows through the electromagnet, this generates a magnetic field that magnetizes the ferromagnetic core. How does having a magnetized core create a stronger magnetic field for the electromagnet? Does its magnetization just "add" to the already existing strength? what are bragging rights and how does that answer the question???
Asked by addinona - Sat Jan 19 17:33:56 2008 - - 2 Answers - 0 Comments
A. The core does not add to the magnetic field, but amplifies it. The relavent formula is B=mu*H. The magnetic field B will be stronger than the free field H (the magnetic field if the iron core were not present) by a factor of the magnetic permeability of the core mu (which for iron is on the order of 1000) until the core material "saturates", and B can go no higher.
Answered by Dr. R - Sat Jan 19 19:46:54 2008
Q. i know that once the current flows through the electromagnet, this generates a magnetic field that magnetizes the ferromagnetic core. How does having a magnetized core create a stronger magnetic field for the electromagnet? Does its magnetization just "add" to the already existing strength? what are bragging rights and how does that answer the question???
Asked by addinona - Sat Jan 19 17:33:56 2008 - - 2 Answers - 0 Comments
A. The core does not add to the magnetic field, but amplifies it. The relavent formula is B=mu*H. The magnetic field B will be stronger than the free field H (the magnetic field if the iron core were not present) by a factor of the magnetic permeability of the core mu (which for iron is on the order of 1000) until the core material "saturates", and B can go no higher.
Answered by Dr. R - Sat Jan 19 19:46:54 2008
Do i need a special type of magnet if i want to build an electromagnet?
Q. If i want to build an electromagnet then do i need a special magnet or not? How would i go about building my own electromagnet?
Asked by Philip - Thu Apr 23 18:13:59 2009 - - 3 Answers - 0 Comments
A. Wire around the metal cause the electromagnetic forces. The wire with an electric current passing through it, generates a magnetic field around it, this is a simple electromagnet. The strength of magnetic field generated is proportional to the amount of current. This should help you out.
Answered by unknown - Thu Apr 23 18:32:17 2009
Q. If i want to build an electromagnet then do i need a special magnet or not? How would i go about building my own electromagnet?
Asked by Philip - Thu Apr 23 18:13:59 2009 - - 3 Answers - 0 Comments
A. Wire around the metal cause the electromagnetic forces. The wire with an electric current passing through it, generates a magnetic field around it, this is a simple electromagnet. The strength of magnetic field generated is proportional to the amount of current. This should help you out.
Answered by unknown - Thu Apr 23 18:32:17 2009
If the current direction is reversed on an electromagnet does the magnetic attraction get reversed also?
Q. If I have an electromagnet that attracts the north pole of a magnet, will the attraction force get reversed (meaning will it attract the south pole) if the current direction is reversed?
Asked by Joel - Mon May 18 12:49:40 2009 - - 2 Answers - 0 Comments
A. Yes. Think of this problem as a question of superposition. So suppose you hypothetically super impose another copy of the electromagnet exactly on top of the first one. i.e. All of the wires of the second magnet are put exactly on top of its corresponding counter part in the first magnet. Now turn your first magnet on, and it'll create a magnetic field in some direction. To solve our problem, we want to turn on our superimposed second magnet in such a way that the magnetic field is 0. One such way (and the only such way) to do this is to turn on the second magnet with the current opposite of the first one. Since all of the corresponding wires are on top of each other and have opposite current, the net current at every point is 0, thus… [cont.]
Answered by SercassaM - Mon May 18 13:00:42 2009
Q. If I have an electromagnet that attracts the north pole of a magnet, will the attraction force get reversed (meaning will it attract the south pole) if the current direction is reversed?
Asked by Joel - Mon May 18 12:49:40 2009 - - 2 Answers - 0 Comments
A. Yes. Think of this problem as a question of superposition. So suppose you hypothetically super impose another copy of the electromagnet exactly on top of the first one. i.e. All of the wires of the second magnet are put exactly on top of its corresponding counter part in the first magnet. Now turn your first magnet on, and it'll create a magnetic field in some direction. To solve our problem, we want to turn on our superimposed second magnet in such a way that the magnetic field is 0. One such way (and the only such way) to do this is to turn on the second magnet with the current opposite of the first one. Since all of the corresponding wires are on top of each other and have opposite current, the net current at every point is 0, thus… [cont.]
Answered by SercassaM - Mon May 18 13:00:42 2009
How do you set up an electromagnet?
Q. Using - a small 9 volt battery - wire - long iron nail - thin copper wire also is that enough or do you need more materials? i need the electromagnet to test the strength of it by changing one variable.
Asked by mixmytape - Sat Mar 24 20:39:26 2007 - - 3 Answers - 0 Comments
A. You just wrap the wire around the nail, lots of times, with at least a couple inches of lead from each end of the wire Touch each end of the wire to the terminals of the battery (one to positive, one to negative), and you've got an electromagnet. I suggest 100 wraps to start. A variable to test would be the number of wraps. Increase or decrease, and see what happens to the power of your magnet. I presume the plain wire is used to test the strength of the magnet?
Answered by Jim S - Sat Mar 24 20:48:28 2007
Q. Using - a small 9 volt battery - wire - long iron nail - thin copper wire also is that enough or do you need more materials? i need the electromagnet to test the strength of it by changing one variable.
Asked by mixmytape - Sat Mar 24 20:39:26 2007 - - 3 Answers - 0 Comments
A. You just wrap the wire around the nail, lots of times, with at least a couple inches of lead from each end of the wire Touch each end of the wire to the terminals of the battery (one to positive, one to negative), and you've got an electromagnet. I suggest 100 wraps to start. A variable to test would be the number of wraps. Increase or decrease, and see what happens to the power of your magnet. I presume the plain wire is used to test the strength of the magnet?
Answered by Jim S - Sat Mar 24 20:48:28 2007
From Yahoo Answer Search: 'Electromagnet'
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The most notable instance of this was in 1973, when Jimmy Gronen was stripped of his title after it was discovered that his car contained an electromagnet . ...
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Tenders are invited for supply of . electromagnet. relay., Location : Columbus,(United States Of America), Last date : 18 August 2009 04:02:53 GMT.
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