A Diffraction Grating A diffraction grating has a line density of 650lines/mm .

Question

A Diffraction Grating

A diffraction grating has a line density of 650lines/mm . This grating produces a 1st order maximum at a distance of 2.52m from the central maximum on a screen which is 5.30m away.

1) What is the wavelength of light being used to perform the experiment?

2) At what distance from the central maximum would the 2nd order maximum be located?

3) What is the highest order possible using the diffraction grating?

A Diffraction Grating

A diffraction grating has a line density of 650lines/mm . This grating produces a 1st order maximum at a distance of 2.52m from the central maximum on a screen which is 5.30m away.

1) What is the wavelength of light being used to perform the experiment?

2) At what distance from the central maximum would the 2nd order maximum be located?

3) What is the highest order possible using the diffraction grating?

Explanation / Answer

path difference = d*sintheta = m*lambda

d*y/D = m*lambda

y = m*lambda*D/d

given for m = 1 , y = 2.52

1/d = 650 lines/mm = 650*10^3

part(1)

2.52 = (1*lambda*5.3* 650*10^3

lambda = 7.314*10^-7 m = 731.4 nm

--------

(2)

for m = 2

y2 = (2*7.314*10^-7*5.3* 650*10^3 = 5.04 m <------answer

-------------

(3)

d*sintheta = m*lambda

sintheta = m*lambda/d

maximum value of sintheta = 1

m = 1*d/lambda = 2.1

highest possible order = 2 <------answer

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

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