A Laboratory in Space Has a Window So an Experiment

question 52

Multiple Choice

A laboratory in space has a window so an experiment can be observed from outside. The apparatus has two light sources, red at one end and blue at the other, that can be switched on at the same time. When the light from either source reaches a detector at the midpoint between the sources, a detector light comes on that is red if the red light reaches it first, that is blue if the blue light reaches first, and is white if both the red and reach the detector at the same time. The experimenter triggers both the blue and the red light sources at the same time, and as a result the white light signals their simultaneous arrival. An observer traveling in a spacecraft at high speed in a direction parallel to the length of the apparatus so as to pass the detector as it turns on during the experiment. What color light does the observer see coming through the window from the detector?

• A) red
• B) white
• C) blue
• D) This requires the length of the apparatus and observer's speed to answer.

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Definitions:

Socially Optimal

The socially optimal point is where the societal benefits of consuming a good or service equal the societal costs of producing it, leading to an efficient allocation of resources.

Marginal Benefit

The increase in utility or enjoyment an individual gets by consuming an additional unit of a good or service.

Marginal Cost

The extra expense associated with creating an additional unit of a product or service.

Streetlights

Outdoor lighting fixtures installed along streets to provide illumination during the night to enhance visibility and safety.