Answer:
t = 88.7 nm
Explanation:
[tex]\lambda[/tex] = wavelength = 532 nm
n = index of refraction of oil = 1.5
t = minimum thickness of oil
m = order
Using the equation
2 n t = (2m + 1) ([tex]\lambda[/tex]/2)
for minimum , m = 0
2 n t = (2(0) + 1)([tex]\lambda[/tex]/2)
[tex]\lambda[/tex] = 4 nt
532 = 4 (1.5) t
t = 88.7 nm