Answer:
1.1 × 10⁻⁴ m = 0.11 mm
Explanation:
d y / L = m λ is the formula that relates the slit separation with all other given quantities here.
y = fringe width = 46 mm = 0.046 m
L = distance to the screen = 2.6 m
Wavelength = λ = 640 nm
Order of the fringe = m = 3
Slit separation = d = m λL / y = (3)(640 × 10⁻⁹ )(2.6) /0.046
= 1.1 × 10⁻⁴ m = 0.11 mm
