Solving Diffraction Grating Homework: Max Wavelength at 11°

[Swan]

Homework Statement

A monochromatic plane wave is normally incident on a diffraction grating with 10⁵ lines/m. For what visible wavelengths would this grating produce a maximum at 11°.

Homework Equations

d*sinθ = m*λ

The Attempt at a Solution

d = 1 x 10^-5 m

I don't get how to actually solve it because i don't know what the m for this situation would be.

 

[tiny-tim]

Hi Swan!

For what visible wavelengths would this grating produce a maximum at 11°.
…
I don't get how to actually solve it because i don't know what the m for this situation would be.

(we usually use "n", not "m")

it can be any whole number …

there may be more than one value for which there is a solution

 

[Swan]

Hi Swan!


(we usually use "n", not "m")

it can be any whole number …

there may be more than one value for which there is a solution

Hello tiny-tim. Thank You for replying. How would i go about solving this question?

 

[tiny-tim]

by using your equation …

what do you get? ​

 

[Swan]

by using your equation …

what do you get? ​

I got at m = 3 and m = 4 the diffraction grating would produce a maximum at 11° at visible wavelengths of 636 nm, 477 nm respectively to m = 3, m = 4.