Preview - Charge Interactions Chem/Phys

Exploring Electric Field Diagrams

Questions

Please answer the questions below.

In the previous page, you brainstormed a few rules for how to draw electric field lines. Here are the rules physicists usually use to draw field lines:

  • Field lines point away from positive charges, and towards negative charges, using an arrow to indicate direction.
  • Field lines are closer together to show when the magnitude of the electric field is stronger, and farther apart when it is weaker.
  • Field lines can't cross. This "Ghostbusters" Rule (don't cross the streams!) exists to show that there is one unique direction for the electric field (and therefore electric force) at each point in space.
  • Electric field "lines" are actually smooth curves, but the Electric field at a particular point (and also the Electric force) is a vector tangent to the electric field lines.

What questions do you have about these rules so far?

Below is an image from the PhET simulation with two positive charges. Using the rules listed above, sketch what you think the field lines would look like for this charge distribution.

Note: Draw your sketch in the sketchpad below

Search for an image of the field surrounding two positive charges. How does your drawing compare to the image you found? 

The PhET simulation does not use electric field lines to depict the field surrounding a charge. How does the PhET simulation show field strength and direction? When might the PhET "field arrow" model or the electric field line model be best to depict the electric field?

The diagram below shows a solid metal conductor with electrons located on the surface, as we saw in Lesson 1 on charge interactions.

Using the rules we discussed, draw what you think the electric field lines look like outside the conductor due to the charges on the surface.  

Note: Draw your sketch in the sketchpad below

In a few sentences, explain your reasoning for why you drew your sketch the way you did in question 6.5.

The diagram below shows a solid metal conductor with electrons located on the surface, as we saw in Lesson 1 on charge interactions.

Using the rules we discussed, draw what you think the electric field lines look like inside the conductor due to the charges on the surface.

Note: Draw your sketch in the sketchpad below

In a few sentences, explain your reasoning for why you drew your sketch the way you did in question 6.7.

How did your field diagram for outside the sphere (Q6.5) compare to inside the sphere (6.7)? Does this difference make sense based on what you know about charge behavior from earlier in the unit?

Notes

These notes will appear on every page in this lesson so feel free to put anything here you'd like to keep track of.