rs fraction grating is ruled with 600 lines/mm. Find the angle at which the firs

Question

rs fraction grating is ruled with 600 lines/mm. Find the angle at which the first order aximum for yellow light (580 nm) will occur b) (5 pts) Find the angle for the second order maximum c) (5 pts) Find the highest order maximum that will be seen with this grating. d) (5 pts) Both a diffraction grating and a Young's double slit apparatus will yield maxima for yellow light at the same angles. Explain why the diffraction grating is more useful for measuring wavelengths than the double slit apparatus.

Explanation / Answer

1. given diffraction grating ruling a = 600 linews / mm

then first order for lambda will be at

theta = lambda*a

where lambda = 580 nm = 580*10^-6 mm

hence

theta = 580*10^-6 * 600 = 0.348 radians

b) for 2nd order maximum, thena = 2*lambda*a

theta-2 = 0.696 radians

c) highest order maxima = nth order

then pi/2 = (n + 1)*a*lambda

n = 3.511

so 3rd order maximum will be seen completely

d) multiple slit diffraction has error dependent on slit width and so does youngs double slit experiment, but multiple slit diffraction has higher order of accuracy in slit width as they have very low slit width, and hence the relative error, due to which the relative error in wavelength measurements is low

Related Questions

Navigate

• Browse (All)
• Browse R
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.