Answer:
t = 94.91 nm
Explanation:
given,
wavelength of the light = 522 nm
refractive index of the material = 1.375
we know the equation
c = ν λ
where ν is the frequency of the wave
c is the speed of light


ν = 5.75 x 10¹⁴ Hz
the thickness of the coating will be calculated using


t = 94.91 nm
the thickness of the coating will be equal to t = 94.91 nm
The mineral with Mohs hardness would be scratched because the mineral with Mohs 7 hardness is stronger than the Mohs 5 mineral. Eventually, that mineral would turn into dust if you kept rubbing it.