A slit has a width of W1=2.3E-6m. When light with awavelength of =510nm passes through this slit, the width ofthe central bright fringe on a flat observation screen has acertain value. With the screen kept in the same place, this slit isreplaced with a second slit (width W2), and a wavelength2=740nm is used. The width of the central brightfringe on the screen is observed to be unchanged. FindW2. I'm not sure where to start. A slit has a width of W1=2.3E-6m. When light with awavelength of =510nm passes through this slit, the width ofthe central bright fringe on a flat observation screen has acertain value. With the screen kept in the same place, this slit isreplaced with a second slit (width W2), and a wavelength2=740nm is used. The width of the central brightfringe on the screen is observed to be unchanged. FindW2. I'm not sure where to start.
Explanation / Answer
in both cases . W sin = where sin represents the width of thecentral fringe . So youhave Wsin = firstwavelength and . Wsin = secondwavelenth . divide equations: W2 / W1 = 2 /1 W2 / 2.3 x 10-6 m = 740 / 510 . W2 = 3.337 x10-6 m is the width of thesecond slit