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Previously, we've learned about the electric field of a point particle. Often, when analyzing physical systems, it is the case that we're unable to analyze each individual particle that composes an object and need to therefore generalize collections of particles into shapes (in this case, a rod) whereby the mathematics corresponding to electric field calculations can be simplified. This can essentially be done by adding up the contributions to the electric field made by parts of an object, approximating each part of an object as a point charge.
Previously, we've learned about the electric field of a point particle. Often, when analyzing physical systems, it is the case that we're unable to analyze each individual particle that composes an object and need to therefore generalize collections of particles into shapes (in this case, a rod) whereby the mathematics corresponding to electric field calculations can be simplified. This can essentially be done by adding up the contributions to the electric field made by parts of an object, approximating each part of an object as a point charge.
=== The System in Question ===
As discussed in the previous section, we're considering a system
abstracted from the particle model we're familiar with, therefore we will
make the generalization that our rod of length L has a total charge of
quantity Q. For this generalization, we will need to assume that the rod
is so thin that we can ignore its thickness.
[image 1]
Since the electric field produced by a charge at any given location is
proportional to the distance from the charge to that location, we will
need to relate the observation location to the source of the charge, which
we will consider the origin of the rod. To do that, we will need to divide
the rod into pieces of length \delta y each containing a charge \delta Q.
In the image below, you can see what this looks like and the relation that
can be found between the observation location and the source, forming the
distance vector \vect{r}.
[image 2]
By the pythagorean theorem, we can find the vector \vect{r} as follows:
[image 3]
And to find the unit vector in the direction of \vect{r}, \hat{r}, we do as
follows:
[image 4]


===Week 5===
===Week 5===

Revision as of 23:36, 25 November 2018

Georgia Tech Student Wiki for Introductory Physics.

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Physics 1

Week 1

Help with VPython

Vectors and Units

Vectors and Units

Week 2

Week 3

Analytic Prediction with a Constant Force

Week 4

Week 5

Conservation of Momentum

Week 6

Week 7

Week 8

Work by Non-Constant Forces

Week 9

Week 10

Choice of System

Rotational and Vibrational Energy

Week 11

Different Models of a System

Models of Friction

Week 12

Week 13

Week 14

Week 15

Physics 2

Week 1

Electric field of a point particle

Week 2

Week 3

Week 4

Physics 3

Week 1

Classical Physics

Week 2

Week 3

Week 4

Week 5

Week 6

Week 7

Week 8

Week 9

Molecules

Week 10

Statistical Physics

Week 11

Condensed Matter Physics

Week 12

The Nucleus

Week 13

Week 14