Rocket Velocity and Mass Ratio

In summary, a large rocket with an exhaust speed of v=3000m/s and a thrust of 24 million Newton will blast out 8 thousand kg of mass per second. If the rocket starts from rest in a force-free environment with the same exhaust speed and 90% of its initial mass being fuel and oxidizer, the final velocity can be found by finding the ratio of initial and final masses in the velocity expression.
  • #1
UrbanXrisis
1,196
1
A large rocket with an exhaust speed of v=3000m/s develops a thrust of 24 million Newton.
a. How much mass is being blasted out of the rocket exhaust per second and
b. what is the max speed the rocket can attain if it starts from rest in a force-free environment with v=3000m/s and if 90% of its initial mass is fuel and oxidizer?

a. 8 thousand kg (=24mill/3000)
b. I'm not sure what the question is asking at all
 
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  • #2
Another way to phrase the question would be - if the rocket is 90% fuel mass, then what is its final speed (ignoring gravity)?
 
  • #3
but don't I need the original mass?
 
  • #4
b) Initial and final masses only appear as a ratio in the expression for the rocket velocity.
Find the way in which that ratio appears in the velocity expression.
 
Last edited:

1. What is rocket propulsion?

Rocket propulsion is the process of using a rocket engine to accelerate a spacecraft or object through the atmosphere or into outer space. It is the force that propels a rocket forward and allows it to overcome the force of gravity.

2. How does rocket propulsion work?

Rocket propulsion works by utilizing Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. The rocket engine burns fuel and expels hot gases out of the back of the rocket at high speeds, creating a thrust force in the opposite direction and propelling the rocket forward.

3. What types of rocket propulsion systems are there?

There are two main types of rocket propulsion systems: chemical and non-chemical. Chemical propulsion systems use a chemical reaction to produce thrust, while non-chemical systems, such as electric and nuclear propulsion, use alternative methods to generate thrust.

4. What are the key components of a rocket propulsion system?

A rocket propulsion system consists of a rocket engine, propellant, and a combustion chamber. The rocket engine is responsible for burning the propellant and generating thrust, while the combustion chamber contains the propellant and allows for controlled burning.

5. How is rocket propulsion used in space travel?

Rocket propulsion is essential for space travel as it provides the force needed to overcome the Earth's gravitational pull and propel spacecraft into orbit and beyond. It is also used for trajectory changes and course corrections during a space mission.

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