Discovering the Correct Rocket Mass Ratio for Beginners

In summary, the mass ratio of a rocket is determined by dividing its wet mass by its dry mass, and the wet mass is equal to the total mass of the rocket.
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Dr Wu
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I'd always thought that to find the mass ratio of a given rocket, one simply had to divide the rocket's wet mass (i.e. fuel and propellant) from its total mass. An example: a rocket's total mass = 2,000 tonnes: its wet mass = 1,000 tonnes. Answer: 2. Is this correct? (I'm pretty sure it isn't, but I can't see where I'm going wrong).

PS. More realistically, if the wet mass of a rocket is 2,000 tonnes, and its dry mass is 200 tonnes, does this mean the mass ratio is 10? If so, we're talking about a total mass of 2,200 tonnes. . . right?
 
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  • #2
The wet mass is the total mass.

The mass ratio is simply wet mass divided by dry mass.
 
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Related to Discovering the Correct Rocket Mass Ratio for Beginners

1. What is rocket mass ratio and why is it important?

Rocket mass ratio is the ratio of the initial mass of a rocket (including fuel) to the final mass of the rocket (after all the fuel has been used). It is important because it determines the efficiency and performance of a rocket. The higher the mass ratio, the more thrust a rocket can generate and the longer it can sustain its flight.

2. How do I calculate the rocket mass ratio?

To calculate the rocket mass ratio, you need to know the initial mass of the rocket (including fuel) and the final mass of the rocket (after all the fuel has been used). Then, divide the initial mass by the final mass. The resulting number is the rocket mass ratio.

3. What is the ideal rocket mass ratio?

The ideal rocket mass ratio is different for each type of rocket and depends on various factors such as the desired altitude, payload, and propulsion system. Generally, a higher mass ratio is preferred for longer and more efficient flights, but it also means a heavier rocket and more fuel needed.

4. How does the rocket mass ratio affect the flight of a rocket?

The rocket mass ratio directly affects the thrust, acceleration, and duration of a rocket's flight. A higher mass ratio results in a greater thrust and acceleration, allowing the rocket to reach higher speeds and altitudes. However, a higher mass ratio also means a heavier rocket, which can impact the overall flight performance and stability.

5. Can I change the rocket mass ratio during a flight?

In most cases, it is not possible to change the rocket mass ratio during a flight. The mass of the rocket, including the fuel, is predetermined before launch. However, some advanced rockets may have adjustable thrust systems that can alter the mass ratio during flight to optimize performance.

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