in lorentz force,we knw its the force eacting on the particles,wen they move in a magnetic field,and it is said tat the speed of the particle remains same,but hw is tat possible?are thr any othr possible physical factors wich can effect the speed of the particle,wen projected in a magnetic field?

Question

anonymous · Answer

sry tat's *acting*

anonymous · Answer

its said that the speed of the particle remains the same because the magnetic lorentz 
force always act perpendicular to the magnetic field and velocity.
so the work done by the force $$fscos \theta$$ is zero
hence no change is magnitude of velocity .but it brings about acceleration as it causes circular or helical motion
Now one more thing to mention . when we say lorentz force it is actually the sum of both magnetic and electric force acting on the body .so always do mention magnetic lorentz force if required

anonymous · Answer

From your flemming's left hand rule you should realize that the force exerted on the particle is always perpendicular to the velocity. You can also use the formula:
$$F=qv \times B$$ to tell.

anonymous · Answer

@vicky-so u said lorentz force is the sum of the magnetic and electric force on the body,so is thr any chance tat they can cancel,out thus makin the force zero?

anonymous · Answer

Yes at times they can cancel each other 
Two mutually perpendicular magnetic and electric fields are basically used in velocity selectors(instrument used to select particles with certain velocities )
The fields are adjusted so as to make the force acting on particles with required velocity zero and by allowing them to pass undeflected where as the other particles are deflected away

anonymous · Answer

thnxxx