Animations for Teaching

This application was developed for EEL4471 (Spring 2017) and incorporated into a pre-laboratory assignment in EEL3472C (Lab 9).

Gap in student knowledge: Understanding this concept requires the capability to visualize how two perpendicular electric field waves (that vary with time) interact to create polarization. In real life, only the effect of the interaction can be observed.

How this animation bridges the gap: This animations allows students to see the perpendicular electric field waves (to the left), change their parameters (dialog boxes to the right), and see the effects on polarization as a function of time and position (to the right).

Implementation:

EEL4471: Assigned to supplement a homework problem - arrive at mathematical solution to a problem and verify the answer visually.

EEL3472C: Assigned as a part of pre-lab 9 - introduced the concept of polarization.

Technical Summary:

Students can enter enter x and y components of electric field of a uniform plane wave traveling in the +z direction and study the resulting polarization. The figures on the left hand side of the application window depict the x component of the E field (top) and y component of the E field (bottom). The amplitudes of both components and the phase offset of the y component can be independently controlled through the dialog boxes in the bottom right side of the application. The figure on the top right shows the time varying tip of the electric field for a constant value of z. The shape traced by the red curve is the nature of polarization of the wave.

This application was developed for EEL4471 (Spring 2017).

Gap in student knowledge: Interaction between a charged particle with a certain velocity and a static magnetic field is described by a mathematical equation involving a cross-product. This mathematical expression is difficult to visualize.

How this animation bridges the gap: Allows students see how a force acts on a charged particle moving in a magnetic field and changes its direction of motion continuously.

Implementation:

EEL4471: Assigned to supplement a homework problem - Students were instructed to study specific scenarios namely the force when charge is stationary, when the charge has a velocity perpendicular to the magnetic field, and when the velocity of the charge is randomly oriented.

Technical Summary:

The figure in the top portion of the application window displays the path traced (in blue) by a charged particle (red) for a certain set of conditions. The magnetic field can be changed by changing dialog boxes corresponding to "B" . The figure on the bottom right displays the entered magnetic field. The initial velocity of the charged particle can be changed in the dialog boxes corresponding to "v".

This application was developed for EEL4471 (Spring 2017) and incorporated into a pre-laboratory assignment in EEL3472C (Lab 11).

Gap in student knowledge: To simplify equations, the textbook does not include the time varying component in the expression for standing waves and plots the standing wave as a static picture (bottom right of fig - phasor voltage). But in real life, the standing wave is time varying (bottom left of fig) and students often misunderstand the concept.

How this animation bridges the gap: This animations allows to see how the standing wave is actually created due to interference between incident and reflected waves.

Implementation:

EEL4471: A previous version of this animation was assigned as part of homework

EEL3472C: Assigned as a part of pre-lab 11 - introduced the concept of standing waves.

Technical Summary:

Students can change the values for the load impedance (ZL) using the sliders, observe the incident wave (red), reflected wave (blue) and total voltage wave (green - bottom left). From this, students can relate to the standing wave pattern in the phasor domain on the transmission line (green - bottom right), and check the value of the reflection coefficient at the load (gamma).