Yellow Light Is Viewed by Reflection from a Thin Vertical $\lambda$

question 7

Multiple Choice

Yellow light is viewed by reflection from a thin vertical soap film. Let $\lambda$ be the wavelength of the light within the film. Why is there a large dark space at the top of the film?

• A) no light is transmitted through this part of the film
• B) the film thickness there is \(\lambda\)/4
• C) the light reflected from exactly one of the two surfaces undergoes a 180 \(\degree\) phase change
• D) the film is too thick in this region for thin film formulas to apply
• E) the reflected light is in the infrared

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Definitions:

Narrow Definition

The narrow definition refers to a specified or limited interpretation of a term, focusing on a specific aspect or characteristic, excluding broader contexts or meanings.

M1

The narrow measure of the money supply, consisting of currency and coins held by the nonbanking public, checkable deposits, and traveler’s checks.

M1

M1 is a category of the money supply that includes all physical money like coins and currency, as well as demand deposits and other liquid assets held by the central bank.

M2

A measure of the money supply that includes all elements of M1 (such as cash and checking deposits) plus "near money" like savings deposits, money market securities, and other time deposits, which are less liquid and not as easily converted to physical cash.