Answer:
[tex]a=0.0947mm[/tex]
Explanation:
Given data
λ=680nm
L=5.5m
ω=7.9cm=0.079m
To find
Width of slit a
Solution
As the single slit of width a has a bright central maximum of width:
ω=2λL/a
a=2λL/ω
Substitute the given values
So
[tex]a=\frac{2*680*10^{-9}m*5.5m}{0.079m} \\a=9.47*10^{-5}m\\or\\a=0.0947mm[/tex]