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# What's the difference between the motor effect and electromagnetic induction?` watch

1. Hi, I've been stuck on the motor effect and electromagnetic induction for a while, and I don't understand what the differences are? Can someone please explain briefly what they do and their differences please.
Thanks for any help
2. Electromagnetic induction, by definition, is the creation of a potential difference across a conductor which is experiencing a change in magnetic field. In order to see this we can move a magnet inside a coil of wire, causing a potential difference to be induced. The movement of the magnet creates a current, too. The same thing can be done if you turn a magnet end to end in a coil of wire. This is how generators work. The motor effect, however, is when a current-carrying wire in the presence of a magnetic field experiences a force. This can be used to create movement, such as in the simple electric motor.

Therefore, the difference between the two is that electromagnetic induction is a creation of potential difference, thus a current, which allows electricity to be generated (as it causes a current to flow in the wire that the coil is made of). However, the motor effect is when wires already carrying currents in magnetic fields experience forces which act on them, which is the principle behind electric motors (hence the name).

I'm not sure if this was what you were looking for. I struggle with both topics too, so if you need any more help you're welcome to ask
3. One necessitates motion (motor effect, which produces physical force) and one is stationary (induction, which procudes voltage).

The motor effect can be seen in the operation of a galvanometer. If you magnetize a needle and suspend it on a thread at right angles to a vertical coil with, say, ten turns, and then pass a current through the coil, the magnetic fields will interact and cause the needle to move. That's the basis for ammeters and other such equipment.

Induction is where the movement of a magnetic field brushing across a wire or (most often) a coil causes a current to pass through the coil. So, if you wind a coil of fifty turns around a nail, wrap tape around it, and then wind another coil of five hundred turns on top of that, you have a very simple form of transformer. When you pass a current through the first coil (with fifty turns, called the primary winding), the nail becomes an electromagnet (as we know). When the current is removed, the magnetic field collapses and, as it brushes through the secondary winding, induces a current of proportianately higher voltage to that which was applied to the primary (eg. with this coil, an AA cell at 1.5 volts will produce approximately 15 volts).

Related trivia: induction coils were used as the first radio transmitters 120 years ago - that's how I know this, I built one entirely from scratch
4. (Original post by MersennePrime)
Electromagnetic induction, by definition, is the creation of a potential difference across a conductor which is experiencing a change in magnetic field. In order to see this we can move a magnet inside a coil of wire, causing a potential difference to be induced. The movement of the magnet creates a current, too. The same thing can be done if you turn a magnet end to end in a coil of wire. This is how generators work. The motor effect, however, is when a current-carrying wire in the presence of a magnetic field experiences a force. This can be used to create movement, such as in the simple electric motor.

Therefore, the difference between the two is that electromagnetic induction is a creation of potential difference, thus a current, which allows electricity to be generated (as it causes a current to flow in the wire that the coil is made of). However, the motor effect is when wires already carrying currents in magnetic fields experience forces which act on them, which is the principle behind electric motors (hence the name).

I'm not sure if this was what you were looking for. I struggle with both topics too, so if you need any more help you're welcome to ask
Ahh, thank you so much! I understand it now yeh aha this was what I was looking for thanks for the help
5. (Original post by Tootles)
One necessitates motion (motor effect, which produces physical force) and one is stationary (induction, which procudes voltage).

The motor effect can be seen in the operation of a galvanometer. If you magnetize a needle and suspend it on a thread at right angles to a vertical coil with, say, ten turns, and then pass a current through the coil, the magnetic fields will interact and cause the needle to move. That's the basis for ammeters and other such equipment.

Induction is where the movement of a magnetic field brushing across a wire or (most often) a coil causes a current to pass through the coil. So, if you wind a coil of fifty turns around a nail, wrap tape around it, and then wind another coil of five hundred turns on top of that, you have a very simple form of transformer. When you pass a current through the first coil (with fifty turns, called the primary winding), the nail becomes an electromagnet (as we know). When the current is removed, the magnetic field collapses and, as it brushes through the secondary winding, induces a current of proportianately higher voltage to that which was applied to the primary (eg. with this coil, an AA cell at 1.5 volts will produce approximately 15 volts).

Related trivia: induction coils were used as the first radio transmitters 120 years ago - that's how I know this, I built one entirely from scratch
Thank you very much! This was very interesting to read and wow how cool! That's incredible that you built one
6. (Original post by vincentvangogh)
Thank you very much! This was very interesting to read and wow how cool! That's incredible that you built one
You're welcome I thought about doing a write-up on it some time and maybe some pictures, if you're interested I can let you see.
7. (Original post by Tootles)
You're welcome I thought about doing a write-up on it some time and maybe some pictures, if you're interested I can let you see.
Ah of course thanks!! It'd be super interesting to read about it and to see it

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