An electron, denoted by the red circle (position is in meters and time is in seconds), is shown in 4 animations. In which animations can the electron produce radiation? 

An oscillating point charge will produce a radiation field as shown in the above animation.  In what direction is the radiation a maximum?   Start

The animation shows how static electric field lines from a positive point charge produce a radiation field if the charge is caused to oscillate.  Notice how the electric field lines form waves that move away from the charge.  What is the direction of the magnetic field associated with the waves to the right of the charge?   Start

The animation purports to show an E&M wave propagating in the z direction. The lengths of the E and B vectors are arbitrary, only direction and relative phase are important. You may click-drag in the animation to change the viewing angle. Which is the electric field?  Start

Four animations purport to show an E&M wave propagating in the z direction.  The electric field is displayed in blue and the magnetic field is displayed in red.     The lengths of the E and B vectors are arbitrary, only direction and relative phase are important. You may click-drag in the animation to change the viewing angle. Which animation correctly displays a physically acceptable configuration for these fields? 

The animation shows an E&M wave propagating in the z direction and passing through a polarizer.  The gray square represents the polarizer and the black line represents the direction of polarization. The magnetic field is not shown.  You may click-drag in the animation to change the viewing angle.  What animation shows a physical result?  

The animation shows an E&M wave propagating in the z direction and passing through a polarizer.  The gray square represents the polarizer and the black line represents the direction of polarization. The magnetic field is not shown.  You may click-drag in the animation to change the viewing angle.  What animation shows a physical result?     

The animation shows an E&M wave propagating in the z direction and passing through a polarizer.  The gray square represents the polarizer and the black line represents the direction of polarization. The magnetic field is not shown. You may click-drag in the animation to change the viewing angle. What fraction of the energy passes through the polarizer?    Start

The animation shows an E&M wave propagating in the z direction and passing through a polarizer.  The gray square represents the polarizer and the black line represents the direction of polarization. The magnetic field is not shown.  You may click-drag in the animation to change the viewing angle. What fraction of the initial electric field amplitude passes through the polarizer?    Start

The animation shows an E&M wave propagating in the z direction and passing through two polarizers.  The gray square represents the polarizer and the black line represents the direction of polarization. The magnetic field is not shown.  You may click-drag in the animation to change the viewing angle.  What fraction of the energy passes through the polarizer?   Start

The animation shows an E&M wave propagating in the z direction.  The electric field is displayed in blue and the magnetic field is displayed in red.   The lengths of the E and B vectors are arbitrary, only direction and relative phase are important. You may click-drag in the animation to change the viewing angle. What is the direction of polarization?   Start