Question

Early investigators (including Thomas Young) measured the thickness of wool fibers using diffraction. One early instrument used a collimated beam of 560 nm light to produce a diffraction pattern on a screen placed 30 cm from a single wool fiber. 

Part A

If the fiber's diameter was 13 um, what was the width of the central maximum on the screen? Express your answer with the appropriate units. 

Answer 1

the widthof the central maxima istwice thedistanceto thefirst minima the angular postion of first minimum light beam wavelength-X-560nm distance to thescreen D-30 cm diamter of the fiber- d 13m si θ-_-_ order of the minima n 1,-2 d D for n -l ;y,-postion of first minima from centre, - postion of first centre, d D 2ND > width of central max ma-v-2y,- we plug the valuesin hand while using the relation 22D w= 2y,-20=0.02585m-12:585cm]