Question 128: Motion in 2D & Vectors

Question

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 :

Accepted Answer

AB = V
P
$$ 	imes $$ t
BC = Vt
cos60
o
= $${{AB} \over {BC}}$$
$${1 \over 2} = {{{V_P} 	imes t} \over {Vt}}$$
V
P
= $${V \over 2}$$

Answer

$${{\sqrt 3 } \over 2}$$v

Answer

$${{2v} \over {\sqrt 3 }}$$

Answer

v

Answer

$${v \over 2}$$

Motion in 2D & Vectors

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 :

Choose the correct answer: