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:

Earnings Reinvested

Profits that are not paid out as dividends but are instead reinvested in the business to fund growth or pay down debt.

Retention Rate

A metric indicating the percentage of earnings not paid out as dividends but retained by the company for reinvestment.

Plowback Ratio

The proportion of the firm’s earnings reinvested in the business (and therefore not paid out as dividends). The plowback ratio equals 1 minus the dividend payout ratio.

Expected Growth Rate

The anticipated rate at which an investment, economy, or other financial entity will grow over a certain period.