JEE Main 2013 — Waves and Sound Question with Solution
JEE Main 2013 (09 Apr Online)
Question
An engine approaches a hill with a constant speed. When it is at a distance of , it blows a whistle whose echo is heard by the driver after seconds. If the speed of sound in air is , then the speed of the engine is :
Choose an option
Show full solutionCorrect option: D
Correct answer
D
Step-by-step explanation
Let after engine at point $\begin{aligned} & \mathrm{t}=\frac{\mathrm{AB}}{330}+\frac{\mathrm{BC}}{330} \\ & 5=\frac{0.9 \times 1000}{330}+\frac{\mathrm{BC}}{330} \\ & \therefore \mathrm{BC}=750 \mathrm{~m} \end{aligned}$ Distance travelled by engine in Therefore velocity of engine
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This is a previous-year question from JEE Main 2013, covering the Waves and Sound chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.