Ans: Minimum thickness of the film = t = 94nm
Explanation:
The condition for the (constructive) interference is:
[tex]2nt = ( m + \frac{1}{2})\lambda [/tex] --- (1)
n = refractive index = 1.33
t = thickness of the film = ?
m = integer = for minimum thickness, m = 0
λ = wavelength = [tex] \frac{c}{f} [/tex] = [tex] \frac{3*10^8}{6*10^{14}} [/tex] = [tex]5 * 10^{-7}m[/tex]
Plug in the values in equation (1):
[tex]2nt = (0 + \frac{1}{2} )\lambda [/tex]
[tex]t = \frac{\lambda}{4n} [/tex]
[tex]t = \frac{5*10^{-7}}{4*1.33} [/tex]
[tex]t = 94*10^{-9}m[/tex]
t = 94nm
