A Ruby Laser Can Deliver a 4

question 62

Multiple Choice

A ruby laser can deliver a 4.33-J pulse in approximately 50 nanoseconds.The wavelength of the light is 694 nm.At least how many atoms within the ruby rod had to be excited to allow this high-energy laser pulse? (h = 6.63 × 10−³⁴ J⋅s,c = 3.00 × 10⁸ m/s,1 eV = 1.6 × 10−¹⁹ J,and 1 nm = 10−⁹ m)

• A)3.5E+18
• B)3.0E+17
• C)1.5E+19
• D)1.5E+21
• E)​1.1E+18

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Definitions:

Allergy

An allergy is a hypersensitive immune response to a substance that is normally harmless to most people, such as pollen, food, or pet dander.

Severe Cough

A forceful release of air from the lungs under high pressure, often persistently strong and indicative of a significant respiratory condition.

Common Cold

A viral infection typically causing runny nose, sore throat, cough, and sneezing.

Influenza

A highly contagious viral infection that affects the respiratory system, characterized by symptoms like fever, cough, and body aches.