DANB Radiation Health and Safety (RHS) Practice Exam

Disable ads (and more) with a membership for a one time $2.99 payment

Prepare for the DANB Radiation Health and Safety Exam. Study with our comprehensive quizzes featuring multiple-choice questions, detailed explanations, and expert tips to excel in your certification journey!

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 a vacuum?

186,000 miles per second
299,792 kilometers per second
Both options A and B are correct
Neither A nor B

The correct answer is: Both options A and B are correct

The speed of light in a vacuum is a fundamental constant in physics, often denoted by the symbol 'c.' It is universally accepted to be approximately 299,792 kilometers per second. This value is frequently cited in scientific literature and is crucial for understanding various physical phenomena, such as the theory of relativity. The value in miles, approximately 186,000 miles per second, is also accurate when converted from the metric measure. Both measures represent the same speed of light but in different units of measurement. Therefore, both options presented are indeed correct as they describe the same speed using different numerical values based on different unit systems. This dual validity underscores the importance of understanding both metric and imperial units in scientific contexts.