ericmazur / PnPbook

Tracking of typos, errors, and improvements for "The Principles and Practice of Physics"
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field lines ... also reasoning including backtracking #197

Open JohnDenker opened 8 years ago

JohnDenker commented 8 years ago

On page 433 of book II in connection with worked problem 24.1:

The field lines in figure WG24.3 are incorrect. They violate the Maxwell equations. Recall that the spacing between field lines is an indication of field strength (or rather the inverse thereof). The field lines near the midplane are much too close together. This indicates a strong field. This locally strong field means there is a tremendous amount of curl in the field : dEy/dx is huge and is not cancelled by any other contributions.

Important connection:

There has been some discussion of the fact that reasoning is like running a maze; it is not like running laps on a well-lit track. Backtracking is often necessary. That means giving up on a minor sub-goal in order to further the main overall goals.

This exercise can be used to make that point. See also https://www.av8n.com/physics/research-maze.htm and https://www.av8n.com/physics/glorpy-maze.html

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