Erratum: Analysis and Synthesis of Optical Images (Am. J. Phys. 21, 337, 1953)

Shortcut to stationary regimes: A simple experimental demonstration

“…The last condition is important since the stationary trajectory we aim at reaching is solution of the second order linear differential equation (4). We add the two following constraintsq(0) = 0,q(0) = 0 to ensure a smooth initial variation of the charge.…”

“…In most basic textbooks in electricity, the use of time-dependent voltage source to drive a circuit is reduced to a sinusoidal driving 1 . This is of paramount importance to introduce the concept of filtering in Fourier space 2 , a technique that appears in many other fields of physics 3 including wave optics 4 . Such time-dependent circuits also provide an opportunity to train the students on solving linear differential equations, and gives the opportunity to discuss the mechanical equivalent of an inductance, a capacitor or a resistor.…”