Two Spaceships Are Traveling Past Earth at 90% of the Speed

question 340

Multiple Choice

Two spaceships are traveling past Earth at 90% of the speed of light in opposite directions (i.e.,they are approaching each other) .One turns on a searchlight,which is seen by scientists aboard the other.What speed do the scientists measure for this light (c = speed of light in a vacuum) ?

• A) 1.9 c (equal to c + 0.9 c)
• B) 1.8 c (equal to 2 × 0.9 c).
• C) c
• D) 0.9 c

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Definitions:

Quantity

The amount or number of a material or immaterial entity that is considered as a unit or in a measurable amount.

True Proposition

A statement that accurately describes a fact or situation, aligning with reality.

Subject Class

A group or category that shares certain characteristics, forming the subject of logical or philosophical analysis.

Quantity

The amount, number, or extent of something, often measurable.