Concept:The velocity of sound in gases depends on internal restorative and inertial forces.
Formula:$$ v = \sqrt{\frac{\gamma P}{\rho}} $$
Solution:- According to the ideal gas law, pressure (\( P \)) and density (\( \rho \)) are directly proportional as long as the temperature is stable.
- If atmospheric pressure drops (like at a higher altitude), the air density drops by the exact same proportional factor.
- Because both variables shift identically, the ratio of \( P/\rho \) remains completely mathematically constant.
- Thus, ambient pressure alone has absolutely zero effect on the speed of sound.
Why other options are incorrect:Speed is heavily dependent on Density (lighter gases transmit faster), Temperature (hotter gases transmit faster), and Moisture (humid air is less dense, increasing speed).
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