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JEE Main201912 Jan 2019Morning ShiftPhysicsMathematics in PhysicsActual

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 v is the speed of sound, speed of the plane is:

Options

  1. A2 v 3
  2. Bv
  3. Cv 2
  4. D3 2 v

Correct answer

C. v 2

Step-by-step solution

d v s = d c o s 60 o v a v a = v s 2 = v 2

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