Light from a HeNe laser (632.8 nm wavelength) is directed upon a human hair,in an attempt to measure its diameter by examining the diffraction pattern.The hair is mounted in a frame 7.5 m from a wall and the central diffraction maximum is measured to be 14.6 cm wide.What is the diameter of the hair?
A) 65 microns
B) 32.5 microns
C) 43.3 microns
D) 86.6 microns

Question

Quizplus · Accepted Answer

The diameter of the hair can be calculated using the formula:d = 2.44 * lambda * L / wwhere:d is the diameter of the hairlambda is the wavelength of the lightL is the distance from the hair to the wallw is the width of the central diffraction maximumPlugging in the given values, we get:d = 2.44 * 632.8 nm * 7.5 m / 14.6 cmd = 65 microns

Light from a HeNe Laser (632