- #1
WarOwk
Homework Statement
A rocket, weighing 43,600N, has an engine that provides an upward force of 120,000N. It reaches a maximum speed of 860 m/s. For how much time must the engine burn during launch in order to reach this speed?
Homework Equations
p=m*Δv
i=F*t
The Attempt at a Solution
I started by using 120,000N as the Force. I used 43,600 as the mass and 860 as the velocity. I multiplied 43,600 by 860 to get 37,496,00. I then divided the momentum(37,496,000) by the force(120,000) to solve for time. The solution I got was 312.5 seconds. Our teacher has already given us the answer to the problem which is 31.8 seconds, but there is an upcoming test and I would like to know how he got this answer.