When sound is produced in an aeroplane with a velocity of 200 m/s horizontally its echo is heard after 10sqrt(5)seconds. If velocity of sound in air is 300 ms^(-1)the elevation of aircraft is

When sound is produced in an aeroplane with a velocity of 200 m/s hori

1.	When sound is produced in an aeroplane with a velocity of 200 m/s horizontally its echo is heard after 10sqrt(5)seconds. If velocity of sound in air is 300 ms^(-1)the elevation of aircraft is
Answer» 250 m `250 sqrt(5)` m 1250 m 2500 m SOLUTION :Time for the ECHO `=10sqrt(5)s` (i.e. For sound to travel ABC) Velocity of the plane = 200 m/s OC `=200 xx 5sqrt(5) = 2236`m BC = velocity of sound ` xx 5sqrt(5)` `rArr` BC `=300 xx 5sqrt(5) = 3354`m `therefore OB = sqrt(BC^(2) - OC^(2))` `rArr OB ~= 2500 m` The plane is 2500 m abvoe the ground.

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When sound is produced in an aeroplane with a velocity of 200 m/s horizontally its echo is heard after 10sqrt(5)seconds. If velocity of sound in air is 300 ms^(-1)the elevation of aircraft is

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