The Critical Angle in Air for a Particular Type of Glass

question 26

Multiple Choice

The critical angle in air for a particular type of glass is 39.0°.What is the speed of light in this class glass? (c = 3.00 × 10⁸ m/s)

• A) 1.97 × 10⁸ m/s
• B) 1.94 × 10⁸ m/s
• C) 1.91 × 10⁸ m/s
• D) 1.89 × 10⁸ m/s
• E) 2.00 × 10⁸ m/s

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Definitions:

Machine Hour

A unit of measure representing one hour of operating time for a machine, used in allocating manufacturing costs.

Fixed Cost

Operating expenses that do not change in proportion to the level of production or sales activity, such as rent or salaries.

Variable Costs

Expenses that fluctuate in proportion to the activity of a business.

Activity Level

A measure of the volume of production or operations, often influencing costs and revenues in a business.