Not sure.can you give me a clue?
Answer:
λ = 5.85 x 10⁻⁷ m = 585 nm
f = 5.13 x 10¹⁴ Hz
Explanation:
We will use Young's Double Slit Experiment's Formula here:

where,
λ = wavelength = ?
Y = Fringe Spacing = 6.5 cm = 0.065 m
d = slit separation = 0.048 mm = 4.8 x 10⁻⁵ m
L = screen distance = 5 m
Therefore,

<u>λ = 5.85 x 10⁻⁷ m = 585 nm</u>
Now, the frequency can be given as:

where,
f = frequency = ?
c = speed of light = 3 x 10⁸ m/s
Therefore,

<u>f = 5.13 x 10¹⁴ Hz</u>
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