https://www.superphysics.org/research/fresnel/light/ Recent content in Fresnel's Prize Memoir On The Diffraction Of Light on Superphysics Hugo en Tue, 30 May 2023 00:00:00 +0000 https://www.superphysics.org/research/fresnel/light/section-02/ Tue, 30 May 2023 00:00:00 +0000 https://www.superphysics.org/research/fresnel/light/section-02/ <!-- 33. In the first section of this memoir I have shown that --> <p>The following cannot explain the phenomena of diffraction:</p> <ul> <li>the corpuscular theory</li> <li>the principle of interference when applied only to direct rays and to rays reflected or inflected at the very edge of the opaque screen</li> </ul> <p>The proper theory is in the terms of waves. This is based on:</p> https://www.superphysics.org/research/fresnel/light/section-02c/ Tue, 30 May 2023 00:00:00 +0000 https://www.superphysics.org/research/fresnel/light/section-02c/ <ol start="41"> <li>From this general expression it is seen that the resultant intensity of the light vibrations is equal to the sum of intensities of the two constituent pencils when they are in perfectagreement and to their difference when they are in exactlyopposite phases, and, lastly, to the square root of the sum of their squares when their phase difference is a quarter of a wave-length, as we&rsquo; have already shown. It thus follows that the phase of the wave corresponds ex- actly to the angular position of the resultant of two forces, a and a&rsquo;. The distance from the first wave to the second is c, to the resultant wave ^-, and from the resultant wave to the/*7T second is c</li> </ol> <ul> <li></li> </ul> <p>; accordingly, the corresponding angles are (* C &rsquo; 2TT., i, and 2ir. i. Let us multiply the equation A A + &rsquo; COS ( 2TT =:A COS i by sin t, and the following equation a&rsquo; sin ( %TT J =A sin i by cos i. Subtracting one from the other, we have a sin i=a&rsquo; sin t 2?r i V which, together with a&rsquo; sin ( 27T j =A sin i, gives the following proportion: I 2?r i: sin i : sin 2?r- : : a : a&rsquo; : A. 42. The general expression, A sin gyff -Y_t|, for the velocity of the particles in a wave produced by the meeting of two others shows that this wave has the same length as its components and that the velocities at corresponding points are proportional, so that the resultant wave is always of the samenature as its components and differs only in intensity that is to say, in the constant by which we must multiply the velocities in either of the components in order to obtain the correspond107 sn</p>