The density of hydrogen is __________ times the density of air?
Correct answer: A. 0.07
- A. 0.07
- B. 1.5
- C. 2.5
- D. 3.5
Explanation
Hydrogen has a relative density of approximately 0.07 compared with air, making it much lighter. Its low density also reduces windage and ventilation losses in high-speed machines.
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