A particle is fired vertically upwards from the surface of earth and reaches a height 6400km. Find the initial velocity of the particle if R = 6400km and g at the surface of earth is 10m//s^2

A particle is fired vertically upwards from the surface of earth and r

1.	A particle is fired vertically upwards from the surface of earth and reaches a height 6400km. Find the initial velocity of the particle if R = 6400km and g at the surface of earth is 10m//s^2
Answer» Solution :`1/2"m"upsilon^2=(mgh)/([1+(h//R)])` hereh = R = 6400 km and `g = 10 m//s^2` so `upsilon^(2)=GH` , i.e. `upsilon=sqrt(10xx6400xx10^(3))=8km //s`