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If I spin a magnet really fast, and put my finger near it, i get no electric shock.

However if i place a wire near that wire it will induce an emf across the wire, if i touch it, will i get a shock?

aka, does the introduction of the wire make it easier for me to get a shock? my intuition says yes, but when i actually think about it, the emf around a path is independant of whether or not an actual wire is there, and the same emf across my body is present if the wire ISNT THERE. imagine e.g a path starting from my finger across my body back to my finger?

So is my intuition correct? or would it have no impact.

the only thing i can think of if it IS the case, is the resistance is lower on the path with the wire so no current? but it still has to travel the same distance in my body

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I am not sure about the last sentence of your question but as far as I can understand your question, the point is that the current is not the same as the emf. The way you get shock is by the current not only by the voltage difference (in this case, emf).

The presence of a conductive wire will make you get shocked easily by touching the wire because the wire works as a good source of charges and currents that try to cancel the emf generated by the spinning magnet.

The presence of the wire makes difference because your body is not a good conductor while the wire (I presume) is a good conductor and the current will prefer the wire path. Yeah, low resistance in the wire.

You can get shocked by the current generated from your body if the magnet is strong enough and spins very fast so that the emf is high enough, though.

== old answer == Air molecules at standard conditions (like 1 atm, 300 K, etc.) works as a good electric insulator and you need high enough emf to generate current. If the emf generated by spinning the magnet is very high so that it can even ionize air, then you can get shocked. In this case, this can be the case that you explained that the electric current can make a loop (not a perfect loop that though). Note also that the distance from the spinning magnet will make emf gradient, that the emf near the magnet will be higher than that at a distance and you can get shocked directly if the magnet spins extremely fast or the magnet is extremely strong.

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  • $\begingroup$ There's no reason air needs to be involved at all- if you change the magnetic field fast enough you could induce current directly inside the body. $\endgroup$
    – Chris ♦
    Jun 1, 2021 at 15:38
  • $\begingroup$ Oh I misunderstood the question. I thought it was about electric spark that one can see... I will modify. $\endgroup$
    – Above Threshold
    Jun 1, 2021 at 15:40
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If I spin a magnet really fast, and put my finger near it, I get no electric shock.

Your assumption is incorrect. A sufficiently large change in magnetic field could induce an electric shock. Of course, it would require you to spin a magnet much, much faster than you could physically do.

Does the introduction of the wire make it easier for me to get a shock?

Assuming the loop isn't much larger than your body, the induced voltage should be similar either way. But you're probably actually more likely to be shocked by the magnetic fields directly because they can bypass the electrical resistance of your skin.

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  • $\begingroup$ I was taught that the shock comes from the voltage and the current. however is the current element of the shock,not the current of the wire, but the current inside my body ? if i were to put each hand on the terminal of a battery, there will be a voltage across my body equal to the battery terminal, but because of the resistance of my body i will barely feel anything. however attaching a wire to that same battery and then touching the wire WILL give me a substantial electric shock? yes or no? in both cases the resistance of my body does not change so i am unsure as to why these are different $\endgroup$
    – jensen paull
    Jun 2, 2021 at 8:38
  • $\begingroup$ @jensenpaull They aren't different. If a battery doesn't give you a shock, attaching a wire won't change anything. You might get burnt from the wire getting hot if you short-circuited the battery, though. (Don't do this, the battery may light on fire or even explode). The current inside your body is the main thing determining whether you feel a shock. Because the resistance of your skin is quite high, small voltages are little threat outside your body. But because your internal resistance is much lower, the same voltages applied inside your body can result in substantial shock. $\endgroup$
    – Chris ♦
    Jun 2, 2021 at 18:03

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