Question

A jet aeroplane travelling at the speed of $500km/hr$ ejects its products of combustion at speed of $1500km/hr$ relative to jet plane. What is the relative velocity of the latter with respect to an observer on the ground?

Answer 1

Given,

Velocity of jet wrt latter$=500km/h$

Velocity of latter wrt jet $=-1500km/h$ ($-ve$ sign indicates the motion in opposite direction)

Velocity of latter w.r.t ground $=500+(-1500)$

$=-1000km/h$

$-ve$ sign shows opposite direction

Hence required Velocity is $1000km/h$