If a 20 W Laser Beam,which Has an Initial Diameter $\times$

question 35

Multiple Choice

If a 20 W laser beam,which has an initial diameter of 2.0 mm,spreads out to a diameter of 2.0 m after traveling 10,000 m,what is the initial intensity of the beam?

• A) 20 \(\times\) 10⁶ W/m²
• B) 6.4 \(\times\) 10⁶ W/m²
• C) 3.2 \(\times\) 10⁶ W/m²
• D) 2.0 \(\times\) 10⁵ W/m²
• E) 1.0 \(\times\) 10⁵ W/m²

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Definitions:

Obsessive Thoughts

Intrusive, unwanted thoughts that often cause distress or anxiety and may lead to compulsive behaviors in an attempt to alleviate the distress.

Obsessive-Compulsive Disorder (OCD)

A mental disorder where individuals experience repetitive, unwanted thoughts (obsessions) and behaviors (compulsions) they feel compelled to perform.

DSM-5

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, a classification and diagnostic tool for mental disorders used by mental health professionals.

Anxious Disorder

A category of mental health disorders characterized by excessive fear, anxiety, and related behavioral disturbances.