3/26/15 - Introduction to Flux

If an electron was sent through a chamber with an electric field, we predicted it's trajectory while traveling.

A dipole is placed in an uniform electric field, we derived some torque equations for the dipole and used our knowledge of dot and cross products.

Some flux lines based on the point charges.

A visual representation of flux, the plate would have no flux since it's parallel to the electric field.

The plate would now have maximum flux since it's perpendicular to the electric field.

We found flux going through a box parallel to 4 sides. Those 4 have 0 flux while the two perpendicular plates have a net flux of 0.

Another groups predicted electric field since my picture went missing.

And the VPython programming for this.

The arrows without their axis being changed by the electric field.

One set of arrows changed by the electric field.

3 sets of arrows changed by the electric field.

3/24/15 - Charge cont.

We rewrite the laws of gravitation except in terms of electrical charge.

The derivation for the electric field formula. We find that it is just the electric force divided by the charge at the position we're finding the field of.

We find the equation to find the electrical field at any position in a 3d space around the point charge.

And here we list out the general steps to find the previous equation for any point charge.

Given our introduction to charge, we try showing what a program can show us based on its calculations.

The program made in VPython, we show the electric field vectors at different positions around the point charge.

We also had the program output the numerical version of the field at each point. However, the points are not labeled in the program.

Here we find the total electric field based on two point charges in a one dimensional field.

The actual calculations for the previous problem.

We then move the charge upward and found that vertical components canceled out, leaving us with only the horizontal components.

Professor Mason's calculations since ours was too messy and disorganized to use.

We found that the electric field is 0 at no where unless you count the infinities. This is due to the point charges having opposite signs. 

Given a rod of uniform charge, we break it up into segments, find the electric field based on that segment and use superposition to find the total electric field. We also found the electric field at a point above the horizontal rod.

Seeing how this would approach an integral, we promptly worked out the integration for the electric field given some variables.

3/21/15 - Introduction to Visual Python Programming.

Over the weekend, Professor Mason had us learn VPyhton from some YouTube videos, and complete the challenge at the end of two videos.

The Vectors1 final output

The Vectors2 final output

The console from the program using the "print" command.

The programming was, overall, very simple in nature and easy to follow. The code for the programs can be found below.

Vectors1:

from __future__ import division

from visual import *

sphere(pos = vector(0,0,0), radius = 1, color = color.red)

arrow(pos = vector(0,0,0), axis = vector(-3,0,0), color = color.blue)

sphere(pos = vector(0,-6,0), radius = 1, color = color.red)

arrow(pos = vector(0,-6,0), axis = vector(3,3,0), color = color.blue)

sphere(pos = vector(-3,-3,0), radius = 1, color = color.red)

arrow(pos = vector(-3,-3,0), axis = vector(0,-3,0), color = color.blue)

Vector2:

from __future__ import division

from visual import *

s1 = sphere(pos = vector(-3,0,0), radius = 1, color = color.red)

s2 = sphere(pos = vector(3,3,0), radius = 1, color = color.red)

s3 = sphere(pos = vector(3,-3,0), radius = 1, color = color.red)

arrow(pos=s2.pos, axis = s1.pos - s2.pos, color = color.blue)

arrow(pos=s1.pos, axis = s3.pos - s1.pos, color = color.blue)

arrow(pos=s3.pos, axis = s2.pos - s3.pos, color = color.blue)

print(s2.color)

3/19/15 - Introduction to Charge

We started off the class with rubbing a balloon on hair and a piece of silk, then attempting to stick it to the class cabinet door.

Our 7-yr old definition of charge...

Our lab experiment with tape that holds charge on its surface.

Out initial poorly made result with both tapes on the table.

Then two pieces of tape were put on top of each other.

The top tapes' interaction with each other.

The bottom tapes' interaction with each other.

The interaction between the top and bottom tape.

Written results and answers to the questions from our lab manual.

A simple trigonometric formula for finding an angle between two points given the distance of both the horizontal component and the length of the string. 

A free body diagram was for the object and we found an equation that gives us the force that is acting on the object.

Force using the law of gravitation and the chart for it as well.

Using LoggerPro, we plotted the displacement of an charged object based on its proximity to another charged object.

We then found the force vs separation distance and found that it has a similar relation to the gravitation law.

Given Coulomb's law, we found the magnitude of the charges on the objects, given they had the same charge. We also found the values if the changes were related but not equal. It is not possible to find the signs of these charges as they could switch places and the result would still be the sane.

Another example with Coulomb's lawm we found the force between two charges given their separation distance and charge value.

A problem based on concept instead of values. We found that if we have charges of equal magnitude and opposite charges, that the force acting on each other would be equal and opposite directions.

A more complicated calculation given that there are now two dimensions. We found the force vector in component form.

Our work for the same problem, however we had to fix an error first.

A Van der Graaf generator that is on and has paper strips attached to it. The strips repel each other due to having the same charge.

Another object with the same charge will also repel the strip.

A foil conductor is placed on top of the Van der Graaf generator so there is no charge being diverted to the paper strips. The foil flew off the top due to having the same charge when the device was powered on.

A Franklin? motor is positioned on top of the Van der Graaf generator and its effects will become apparent when the device is powered on.

The top of the Van der Graaf taken off.

Due to the charge accumulating at the tip of the blades, the forces of the repelling action is diverted off the points which produces a rotary motion.

Our predictions for what would happen when the device was powered on during the two tests.

We see how small gravitational force is compared to electrical forces by finding the answer to the universe or whatever that is a reference to.