A Ruby Laser Can Deliver an 4

question 25

Multiple Choice

A ruby laser can deliver an 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:

Water-Diamond Paradox

A concept in economics that questions why diamonds are more expensive than water despite water being essential for survival and diamonds not.

Marginal Utility

The additional satisfaction or benefit received from consuming one more unit of a good or service.

Marginal Utility

The extra utility or satisfaction that someone attains from the consumption of one more unit of a product or service.

Marginal Utility

The extra pleasure or benefit gained by a consumer from consuming an additional unit of a good or service.