Stationary point charge in increasing magnetic field

AI Thread Summary
A stationary point charge in an increasing magnetic field experiences no magnetic force, as the Lorentz force law indicates that force is dependent on the charge's velocity. Since the velocity of the charge is zero, the force acting on it due to the magnetic field is also zero, regardless of how the magnetic field changes over time. Additionally, if the velocity and magnetic field are parallel, the force remains zero even with changes in the magnetic field. The discussion emphasizes that magnetism involves moving charges and changing electric fields, which do not apply to a stationary charge. Therefore, the conclusion is that a stationary charge does not experience a magnetic force in an increasing magnetic field.
jimmyjets
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hi everyone, if a stationary point charge is placed in an increasing magnetic field, is the force on the charge due to the magnetic field = 0?
because Fb = qv*B and v=0

then how would I derive the magnitude of the force on the charge due to the magnetic field with the magnetic field increasing at dB/dt?
thanks
 
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The Lorrentz force law is actually

F = q \mathbf{v} \times \mathbf{B}

It doesn't matter how your magnetic field is changing, if you have no velocity then you will not have any magnetic force acting on the object. Magnetism, from a relative standpoint, is the study of changing electric fields, which you don't have. It is the study of moving charges. If you don't have any current running through a wire, does it have a magnetic field? No, the charges aren't moving. The same thing applies here, your charge isn't moving so there isn't a field to interact with.

The same is true if the velocity and magnetic fields are parallel, no matter how fast the particle accelerates or how much the magnetic field changes the force will be zero.
 
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