Two Flat Glass Plates Are in Contact Along One End

question 3

Multiple Choice

Two flat glass plates are in contact along one end and are separated by a sheet of paper 5.0 × 10−⁶ m thick at the other end.The top plate is illuminated by a monochromatic light source of wavelength 399 nm.How many dark parallel bands will be evident across the top plate? (1 nm = 10−⁹ m)

• A) 13
• B) 23
• C) 12
• D) 25
• E) ​21

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Definitions:

Bonds

Financial instruments representing loans made by investors to borrowers, typically governments or corporations, with an agreed-upon return.

Obligations

Obligations are duties or commitments legally or morally binding an individual or entity to act or refrain from acting in a certain manner.

Gunpowder

A mixture of saltpeter (potassium nitrate), sulfur, and charcoal (carbon) that when ignited, burns rapidly and is used as a propellant in firearms and as an explosive.

European Warfare

Armed conflict involving European nations, characterized by a series of historical military engagements across the continent and beyond.