3/27/2015 electric dipola and electric flux

The electric filed between 2 opposite charged plate that parallel to each other is some straight line parallel to each other and pointing from positive to negative. When a charged particle enters the system with an intial velocity, electric force will be applied on it and makes its motion like a projectile motion.

We define electric dipola moment as a vector that directed from one particle to another particle. This will be used to solve torque and work done by electric force later.

When there is a system inside the electric field that is made up by 2 differently charged particles, the net force is 0, but the net torque isn't 0, which will cause rotation. Next, we derived that torque is cross product of electric dipola moment and elextric field, P X E, and work done by electric force is dot product of -P and E.

This is the prediction of a minimum work phyton program output. We want to use this program to display the electric field of the system consisted of 2 differently charged particles. Apparently, this is not the correct answer, thus we will modify the program.

This is the prediction we made for the electric field of the system. The red arrow is the total electric field at each point on the circle.

After we modify the program, it shows the distribution of electric field as a 2D distribution. However, we want to show it in a real 3D space, and we continue to modify it. Above all, the output matches our prediction.

After modifying the program, we make it show the distribution of electric field in 3D space, and it matches our prediction, too.

We apply the definition of electric field line. The more electric field line it has in a certain area, the stronger the electric field there is. We then use it to work with electric flux.

Electric flux is how many electric lines pass through the surface. The definition is the dot product between electric field and area. It is also the integral ( EdA ). When the angle between the surface and electric field is 90 degrees, the flux will be 0. Since it is a dot product, it has no direction.

In a cubic, we calculate the electric flux on each surface. When the electric field is parallel to the surface, the electric flux is 0. When electric is normal to the surface, the electric flux maxmizes.