Entry Exam Category: Graduate & Professional Program Admission Exams
Course: Praxis
Exam: Praxis Elementary Science 5005 Practice Test
Practice Question
The speed of light in empty space, that is, a vacuum, is 300,000 km/s. The speed of sound in empty space is:
Answer Choices
- B: greater than 0 but less than 300,000 km/s
- C: 300,000 km/s
- D: greater than 300,000 km/s
Correct Answer: A
Rationale: Sound needs medium, vacuum 0. B,C,D: Sound can't propagate in vacuum.