American Board of Opticianry (ABO) Practice Test

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Prepare for the ABO (American Board of Opticianry) Test with interactive flashcards and hundreds of multiple choice questions. Updated for 2024 to help you excel on exam day

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

Practice this question and more.

What is the speed of light in air?

186,000 miles per second
One meter
One diopter prism
Refraction

The correct answer is: 186,000 miles per second

The correct answer is A, 186,000 miles per second. This is the known speed of light in a vacuum, which is a type of air that contains essentially no matter. None of the other options are directly related to the speed of light in air. B is a unit of length, so while it could be measured in meters, it is not a speed measurement. C is a unit of angle measurement that is used in optics, but it does not represent the speed of light in air. D is a phenomenon that occurs when light enters a new material, causing it to change speed and direction, so it also does not directly answer the question.