anonymous
  • anonymous
A rocket is intended to leave the Earths Gravitational Field.The Fuel in its Main engine is a little less than the amount that is necessary, and an auxiliary engine, only capable of operating for a short time, has to be used as well.When is it best to switch on the Auxiliary engine : at take off, or when the rocket has nearly stopped with respect to the Earth, or does it not matter? Give your reasons.
Physics
  • Stacey Warren - Expert brainly.com
Hey! We 've verified this expert answer for you, click below to unlock the details :)
SOLVED
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
katieb
  • katieb
I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!
anonymous
  • anonymous
Let's consider two things. First, that the main and auxiliary rockets produce a set amount of impulse. Second, that by burning the auxiliary rocket, we reduce the mass of the vehicle. Let's define force and impulse as\[F = {dp \over dt} = {d (m \cdot v) \over dt}\]\[I = \int\limits F dt = \int\limits {dp \over dt} dt = \int\limits dp\]\[\int\limits F dt = \int\limits d(m \cdot v)\] We need to make a couple of assumptions. First, let's say that the main rocket burns fuel at a greater rate than the auxiliary rocket. Second, let's say that the main rocket produces more thrust force than the auxiliary rocket. If we fire the auxiliary rocket at launch, the main engine won't have to carry that additional mass of the auxiliary rocket up into orbit. Therefore, the main engine will be able to create a greater \(\Delta v\) on the vehicle in this case than if it had to carry the auxiliary rocket into orbit. However, if we fire the auxiliary rocket after the main engines burn, the auxiliary rocket will create a greater \(\Delta v\) in this case. I would recommend firing the auxiliary rocket first, since the main engine produces the greatest thrust and longest burn time. Consider that the Space Shuttle fires its auxiliary rockets at the time of launch. NASA probably ran the number correctly when they were asked this same question. There are numerous other reasons why the auxiliary rockets fire first, but these are advanced topics.

Looking for something else?

Not the answer you are looking for? Search for more explanations.