Magnetic field does no work -- true in all branches of physics?

AI Thread Summary
The discussion confirms that magnetic fields do not perform work on charged particles, as the force is always perpendicular to the velocity, preventing changes in kinetic energy. This principle holds true across various branches of physics, including high-energy physics, where only electric fields can alter kinetic energy. Even in relativistic scenarios, magnetic fields serve primarily to steer particle beams rather than change their energy. The conversation also notes that while magnetic fields do not do work, they can induce torque in systems like current loops, which can lead to kinetic energy changes. Overall, the consensus is that magnetic fields do no work in all branches of physics.
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The force on a charged particle that is moving through a magnetic field is explained in introductory physics textbooks. The magnetic field cannot change the kinetic energy of the charged particle because the force from the magnetic field is always perpendicular to the velocity, so no work is done.

My question: Is that fact true in all branches of physics, such as high energy physics?
 
Physics news on Phys.org
Synchrotron radiation might be of your interest though I am not qualified to explain it.
 
anuttarasammyak said:
Synchrotron radiation might be of your interest though I am not qualified to explain it.

Hi. Thank you for the recommendation.

I studied particle beam accelerators, and those textbooks also state only the electric fields can be used to change the kinetic energy of the charged particle being accelerated. The magnetic fields do no work, even in situations when the charged particle's speed is relativistic. (The magnetic fields are used to steer the particle beam).

So, my thought is that magnetic fields do no work in all branches of physics. Even esoteric realms of which I am ignorant.

Please correct me if I am wrong about that.
 
It might interest the OP that a current loop and/or a magnetic moment in a magnetic field experiences a torque which can result in an increase in kinetic energy.
 
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