A Piece of Glass Has a Thin Film of Gasoline

question 6

Multiple Choice

A piece of glass has a thin film of gasoline floating on it.A beam of light is shining perpendicular on the film.If the wavelength of light incident on the film is 560 nm and the indices of refraction of gasoline and glass are 1.40 and 1.50,respectively,what is the minimum nonzero thickness of the film to see a bright reflection?

• A) 500 nm
• B) 400 nm
• C) 300 nm
• D) 200 nm
• E) 100 nm

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Definitions:

Experimental Trials

Controlled tests conducted to study the efficacy or effects of a variable under study, often used in scientific and medical research.

Interrupted Time Series Experiments

Research design involving observations of a given variable over time, both before and after an intervention, to assess the effect of that intervention.

Program Logic Model

A tool used in program evaluation that visually represents the relationships between a program's resources, activities, outputs, and intended outcomes.

Intermediate-term Changes

Transformations or developments that occur over a middle-range period, not immediately but not lasting long enough to be considered long-term.