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When riding at night, a bicycle must have a white headlight visible within __ feet and a red reflector or tailgate visible __ to the rear.

A) 300, 100
B) 500, 200
C) 700, 300
D) 1000, 400

User Krajol
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Final answer:

The question concerns the resolution limits of the human eye for objects at a distance, as applied to bicycle safety lighting at night. It involves calculating the maximum distance at which the human eye can resolve car headlights using physics and the Rayleigh criterion for resolution.

Step-by-step explanation:

The question asked deals with the optical resolution limits of the human eye when observing objects at various distances, specifically as it pertains to bicycle safety at night. According to the concepts of physics, the ability to resolve two points as separate is dependent on the angle of resolution and the wavelength of light. This principle can be applied to understanding visibility distances of bicycle lights at night and is also relevant in optical instruments such as telescopes and microscopes.

In the given scenarios, one can use the Rayleigh criterion for resolution to determine the maximum distance at which car headlights, separated by a certain distance, can be resolved. The criterion states that two point sources are resolvable when the principal maximum of the diffraction pattern of one image coincides with the first minimum of the diffraction pattern of the other. The formula used involves the wavelength of light, the diameter of the pupil through which the light enters and the distance between the light sources.

For the headlights of a car that are 1.3 meters apart, with a pupil diameter of 0.4 cm, and for a typical wavelength of 550 nm (average for visible light), one can calculate the maximum resolution distance. This understanding is crucial for ensuring adequate visibility for nighttime bicycle riders, as the headlight and tail reflector must be visible from distances that allow other road users to see them in time to react safely.

User Darkisa
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