Why won't a magnet exert a force on a stationary charged particle

In summary: Could you please clarify?In summary, a static electric field will exert a force on a stationary charged particle, but a magnetic field from a permanent magnet will not. The difference seems to be that a static electric field is created by electric current flowing through a wire, while a magnetic field from a permanent magnet is not created by current.
  • #1
d4rr3n
53
0
Why is it that a static electric field will exert a force on a stationary charged particle but a magnetic field from a permanent magnet will not?

I am somewhat confused by this because the magnetic field in a permanent magnet is the result of spin charge polarisation which must generate closed electric field lines which wraparound the bar magnet at right angles to the magnetic field.

If we think about an electromagnetic we have electrons flowing through a wire so there is charge which must generate electric field lines again at right angles to the magnetic field. why is it these electric field lines exert no force on a stationary charged particle?

What's different about the nature of these electric fields that one will exert a force on a stationary charged particle but the other wont?
 
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  • #2
No, permanent magnets do not create closed electric field lines that wrap around the magnet. A changing magnetic field generates an electric field, but a static magnetic field (of a magnet) will not generate an electric field.
 
  • #3
So the current flowing through the wire of an electromagnet generates no electric field?
 
  • #4
Khashishi answered for permanent magnets. For an electromagnet, there will be no closed electric field lines outside of the wire coils. It is essentially the same if you are viewing it completely outside of the material.

Remember, electric current is a flow of electric charges, but the net charge is still 0. Electrons aren't added to the wires, just pulled through the coils.
 
  • #5
d4rr3n said:
So the current flowing through the wire of an electromagnet generates no electric field?
A closer analogy is the current flowing through a superconducting loop. Those indeed generate no electric field.
 
  • #6
But a wire has resistance hence there is an electric field set up because there is a voltage drop ie;

Vwire = Iwire X Rwire
 
  • #7
That is precisely what makes a superconducting wire a better analogy for a permanent magnet than a resistive wire. Neither a superconducting wire nor a permanent magnet have an electric field around the current loop.

Of course, it is just an analogy, so it isn't perfect, but it does clearly show that you can have current without E fields.
 
  • #8
Yes, When an emf is induced in the coil than a dynamic field is generate it will create a magnetic field that will cause to generate moving particle and these particles attract stationary particle and they will start to moving in the magnetic field.
 
  • #9
Leesa Johnson said:
Yes, When an emf is induced in the coil than a dynamic field is generate it will create a magnetic field that will cause to generate moving particle and these particles attract stationary particle and they will start to moving in the magnetic field.

I'm sorry, Leesa, but I'm having trouble understanding what you've said here.
 

FAQ: Why won't a magnet exert a force on a stationary charged particle

1. Why won't a magnet exert a force on a stationary charged particle?

According to the Lorentz force law, a charged particle experiences a force in the presence of both a magnetic field and an electric field. However, if the charged particle is stationary, there is no motion to interact with the magnetic field, so no force is exerted.

2. Can a magnet exert a force on a stationary charged particle if the magnetic field is strong enough?

No, the strength of the magnetic field does not affect whether or not a force is exerted on a stationary charged particle. The motion of the particle is what determines if it will experience a force from the magnetic field.

3. If a magnet can't exert a force on a stationary charged particle, how can we observe the effects of magnetic fields on charged particles?

We can observe the effects of magnetic fields on charged particles by observing the motion of the particle when it is in motion. The magnetic force will cause the charged particle to experience a change in direction, and this can be observed through various experiments.

4. What happens if a charged particle is both stationary and in a magnetic field?

If a charged particle is stationary and in a magnetic field, it will not experience any force from the magnetic field. However, if an electric field is present as well, the charged particle may experience a force due to the interaction between the electric and magnetic fields.

5. Why is it important to understand that a magnet won't exert a force on a stationary charged particle?

Understanding that a magnet won't exert a force on a stationary charged particle is important in many fields, including physics and engineering. It allows us to accurately predict the behavior of charged particles in the presence of magnetic fields and design devices that utilize this knowledge, such as electric motors and generators.

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