A Light Beam from a 2

question 6

Multiple Choice

A light beam from a 2.1-mW He-Ne laser has a wavelength of 633 nm.How many photons does the laser emit in one second? (h = 6.626 × 10^-34 J • s,c = 3.00 × 10⁸ m/s)

• A) 6.7 × 10¹⁵
• B) 8.8 × 10¹⁵
• C) 1.1 × 10¹⁶
• D) 1.3 × 10¹⁶

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Definitions:

Aquatic Life Zone

Areas in water bodies, such as lakes, rivers, and oceans, that support life, including various plants, animals, and microorganisms.

Level of Organization

Describes the hierarchy in biology from the atomic and molecular scale up through cells, tissues, organs, organisms, populations, communities, ecosystems, and the biosphere.

Ecosystem

A community of interacting organisms and their physical environment, interconnected through nutrient cycles and energy flows.

Cycling of Energy

The process by which energy is transformed and transferred among organisms and their environment.