A person standing on an open ground hears the sound of a jet aeroplane, coming from north at an angle $60^o$ with ground level. But he finds the aeroplane right vertically above his position. If $\upsilon $ is the speed of sound, speed of the plane is
A$\frac{{\sqrt 3 }}{2}\upsilon $
B$\frac{{2\upsilon }}{{\sqrt 3 }}$
C$\upsilon $
D$\frac{\upsilon }{2}$
JEE MAIN 2019, Medium
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D$\frac{\upsilon }{2}$
d $\mathrm{V}_{\mathrm{P}} \rightarrow$ Speed of plane
$\vee \rightarrow$ Speed of sound
$\vee \cos 60^{\circ}=V_{P}$
$V_{P}=\frac{V}{2}$
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