Which Statements About Electric Field Lines Are True?

AI Thread Summary
The discussion clarifies several truths about electric field lines, confirming that they are always perpendicular to the surface of a conductor and originate from positive charges while terminating at negative charges. It is incorrect to state that the electric field can never be zero or that electric field lines can cross. The movement of charged particles, such as electrons and protons, within an electric field is influenced by their charge; electrons move opposite to the field direction, while protons move in the same direction. Participants express uncertainty about the specifics of particle movement in strong electric fields and suggest using analogies, like magnets, to better visualize these concepts. Understanding the forces acting on charged particles is essential for grasping their behavior in electric fields.
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Which, if any, of the following statements about electric field lines is/are true?

  • The electric field is always perpendicular to the surface outside of a conductor. - TRUE
  • It is not possible for the electric field to ever be zero. - FALSE
  • It is possible for two electric field lines to cross each other. - FALSE
  • If an electron were placed on an electric field line, it would move in a direction perpendicular to the field. - NOT SURE
  • If a proton were placed on an electric field line, it would move in a direction anti-parallel to the field. - NOT SURE
  • If an electron and a positron were in the presence of a very strong electric field, they would move away from each other. - NOT SURE
  • Electric field lines originate on positive charge and terminate on negative charge. - TRUE

I do not completely understand the movement of particles through an electric field. How to electrons and positrons move? What are the answers to the questions I'm not sure about?
 
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"If an electron were placed on an electric field line, it would move in a direction perpendicular to the field."

Have you worked with electrostatics before? Do you know conceptually what happens to an electron when it's being subject to an electric field? If electric forces are hard for you to visualize try and make a similar analogy to magnets

"If a proton were placed on an electric field line, it would move in a direction anti-parallel to the field."

Same reasoning as what I said above. Again, think of them as magnets if it helps you visualize it better.

The last one you have to think about the forces acting on the particles. In this case it's a 'really strong electric field'. I would assume that any force from this field would outweigh any force between the two particles.
 


You are aware of how the electric field is defined - use it to determine the motion of a charged particle in a field. For example, a negatively charged particle like an electron will move to a higher potential, i.e. a direction opposite (anti parallel) to the field lines.
 


What kind of charge does an electron have? Is it positive? -or- Is it negative?
 


force on electron will will cause its motion and the direction that force depends on electric field ... so what it should be now?
 
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