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Two motorcyclists are riding side-by-side at night and the distance between their center-mounted headlights is 1.40 m. (a) If the diameter of the pupil of your eye is 0.460 cm and the wavelength of the light is 600 nm, at what angular separation will the eye resolve the two headlights

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Answer:

θ = 1.591 10⁻² rad

Step-by-step explanation:

For this exercise we must suppose a criterion when two light sources are considered separated, we use the most common criterion the Rayleigh criterion that establishes that two light sources are separated census the central maximum of one of them coincides with the first minimum of the other source

Let's write the diffraction equation for a slit

a sin θ = m λ

The first minimum occurs for m = 1, also field in these we experience the angles are very small, we can approximate the sin θ = θ

θ = λ / a

In our case, the pupil is circular, so the system must be solved in polar coordinates, so a numerical constant is introduced.

θ = 1.22 λ / D

Where D is the diameter of the pupil

Let's apply this equation to our case

θ = 1.22 600 10⁻⁹ / 0.460 10⁻²

θ = 1.591 10⁻² rad

This is the angle separation to solve the two light sources

User Maxim Vladimirsky
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