Physics · 2012
NEET 2012 · Mains · Code C · Q73
A train moving at a speed of 220 ms^-1 towards a stationary object, emits a sound of frequency 1000 Hz. Some of the sound reaching the object gets…
A train moving at a speed of $\displaystyle 220 \mathrm{~ms}^{-1}$ towards a stationary object, emits a sound of frequency $\displaystyle 1000 \mathrm{~Hz}$. Some of the sound reaching the object gets reflected back to the train as echo. The frequency of the echo as detected by the driver of the train is :
(speed of sound in air is $\displaystyle 330 \mathrm{~ms}^{-1}$)
Official answer
(1)
$\displaystyle 5000$ Hz
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NEET (UG) 2012 Physics question, with the answer from NTA’s final answer key. Where our answers come from.