Force Lines and Equipotential lines

AI Thread Summary
Field lines and equipotential lines cannot cross due to the fundamental principles of electromagnetism. If two field lines were to intersect, it would imply that a charged object could move in multiple directions at the same point, which contradicts the nature of electric and magnetic fields. Similarly, equipotential lines represent points of constant potential; crossing lines would indicate different potentials at the same location, which is impossible. The inability for these lines to cross ensures that the direction and strength of fields, as well as potential, remain consistent at any given point. This adherence to the laws of electromagnetism is crucial for understanding field behavior.
figs
Messages
27
Reaction score
0
Field Lines and Equipotential lines

Why can't 2 field lines cross, and why can't 2 equipotential lines cross?

I understand that equipotential lines are perpendicular to field lines. And I see that it'd be impossible to find an equipotential line if two field lines have crossed, since there cannot be two places on field lines where an equipotential line can be found. But I don't know the reasoning of why 2 field lines cannot cross. nor 2 equipotential lines.

Am I correct in saying that field lines don't cross because a magnetic object placed at a point in the field moves only in 1 direction due to attraction or repulsion. If 2 lines crossed, it means the object can move in 2 directions, which is not the case.
 
Last edited:
Physics news on Phys.org
Electric field lines? Magnetic field lines?
Assuming magnetic,, Remember the magnetic field is tangent to the mag. field lines at every point. Thus if two field lines intersected, than that would mean that the magnetic field pointed in two different directions at that point in space, but how can that be?
The same argument goes for Electric field lines?

So yes you are correct( should have read the rest of your post :smile: )
 
Last edited:
Similarly, equipotential lines don't cross because the potential at a point is constant, so if 2 lines crossed, the potential would be different at that point, which is not possible.Yes, you are correct in your understanding of why 2 field lines cannot cross. Field lines represent the direction and strength of the electric or magnetic field at a given point. If 2 field lines were to cross, it would mean that at that point, there are 2 different directions and strengths of the field, which is not physically possible.

Similarly, equipotential lines represent points in a field that have the same potential. If 2 equipotential lines were to cross, it would mean that at that point, there are 2 different potentials, which is not possible. This is because the potential at a point is determined by the work done in moving a unit charge from one point to another, and if there are 2 different potentials at the same point, it would mean that the work done would be different depending on which path is taken, which violates the definition of potential.

In summary, the reason why 2 field lines or 2 equipotential lines cannot cross is because it would result in a violation of the laws of electromagnetism and the definitions of field and potential.
 
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Thread 'A cylinder connected to a hanged mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top