Each Photon in a Beam of Light Has an Energy

question 17

Multiple Choice

Each photon in a beam of light has an energy of 4.20 eV.What is the wavelength of this light? (c = 3.00 × 10⁸ m/s,h = 6.626 × 10^-34 J ∙ s,1 eV = 1.60 × 10^-19 J)

• A)321 nm
• B)103 nm
• C)296 nm
• D)412 nm
• E)420 nm

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Definitions:

Pulmonary Surfactant

A complex mixture of lipids and proteins secreted by cells in the lungs, reducing surface tension and preventing the collapse of alveoli at the end of expiration.

Alveoli

Tiny air sacs in the lungs where gas exchange between the air and blood takes place.

Cohesive Forces

Attractive forces between similar molecules that hold a substance together, such as the attraction between water molecules.

Surface Tension

The elastic tendency of a fluid surface which makes it acquire the least surface area possible, acting like a stretched elastic membrane.