A jet airplane travelling at the speed of ejects its product of combustion at the speed of
relative to the jet plane. The speed of the products of combustion with respect to an observer on the ground is
Velocity of jet plane with respect to ground,
Velocity of products of combustion with respect to jet plane
Velocity of products of combustion with respect to ground is
-ve sign shows that the direction of products of combustion is opposite to that of the plane.
Speed of the products of combustion with respect to ground =