Solved UPSC CDS/OTA Question
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Q · Waves and SoundEasy · 45s
Which of these changes will increase the speed of sound in air? Increase in temperature Increase in humidity Decrease in air pressure Select the correct answer: 24
TopicWaves and Sound
Question Typemultiple choice
DifficultyEasy
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Every step explained — no skipped algebra.
Higher temperature increases molecular motion → higher speed of sound.
Higher humidity lowers air density → higher speed of sound.
Air pressure doesn’t affect speed in air at constant temperature.
32
Final Answer: Option A — 1 and 2 only
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