Two rockets are flying in the same direction and are side by side at the instant their retrorockets fire. Rocket A has an initial velocity of +4800 m/s, while rocket B has an initial velocity of +9000 m/s. After a time t both rockets are again side by side, the displacement of each being zero. The acceleration of rocket A is -16 m/s2. What is the acceleration of rocket B?

1 answer

The distance they flew is the same, in the same time.

da=vi*t+1/2 at^2=4800t-16t^2/2
db=vi*t+1/2 at^2=9000t+at^2 /2

set them equal

t(4800-8t)=t(9000+at/2)
9600-16t=18000+at
t(a+16)= -8400
so you see here, there is no unique solution. The faster B breaks, the sooner the rockets are side by side.

A=-8400/t -16 check my math, it is easy to make an error.