Show Works Please The first order maximum due to a grating when using blue light
ID: 1385661 • Letter: S
Question
Show Works Please
The first order maximum due to a grating when using blue light of wavelength 350 nm is at 12.1 degrees.
a) What is the slit separation in mm for this grating?
b) What are the number of lines/mm in this grating?
c) What is in meters the position y1 on the screen, relative to the central maximum of that same first order maximum if the viewing screen is located 0.30 m to from the slits?
d) What is then in meters the position y2 on the screen, relative to the central maximum of the second order maximum?
Explanation / Answer
a)
dsin(theta)=n*lambda
d=1*350*10-9/sin(12.1)
=350*10-9/0.209
=0.00167mm
b)
no of lines/mm=1/d
=1/0.00167
=598*103linres/mm
c)
y=n*lambda*D/d
=1*350*10-9*0.3/0.00167*10-3
=0.06m
d)
y2=2*lambda*D/d
=2*0.06
=0.12m