Answer:
1524 nm.
Step-by-step explanation:
Angular separation of n th minima is given by the expression
Sin θ = n λ / a
Where λ is wavelength of light used and a is separation between two slits .
a = n λ / sin θ
For a to be minimum, sinθ has to be maximum .
maximum value of sin of any angle is 1 .
so the relation becomes as follows
a = n λ
n = 2 , λ = 762 nm.
a = 2 x 762 nm
= 1524 nm.