Rocket Propulsion Homework: Calculating Travel Time

AI Thread Summary
The discussion focuses on calculating the travel time of a rocket with a payload of 4050 kg and 175,300 kg of fuel, expelling propellant at a speed of 4.3 km/s. The key formula mentioned is related to the rocket's final velocity and mass ratio, but participants note a lack of clarity in the equations and variables used. One user points out a significant error in the fuel weight, emphasizing the importance of accurate data for calculations. There is confusion regarding the necessary parameters to determine the travel time over a distance of 382,000 km. Accurate definitions and equations are crucial for solving the problem effectively.
Psyguy22
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Homework Statement


A rocket in outer space has a payload of 4050.0 kg and 1.753·105 kg of fuel. The rocket can expel propellant at a speed of 4.300 km/s. Assume that the rocket starts from rest, accelerates to its final velocity, and then begins its trip. How long will it take the rocket to travel a distance of 3.82 ·105 km


Homework Equations


V [sub c] ln(m [sub i]/ m [sub f])<br /> <br /> <br /> <h2>The Attempt at a Solution</h2>
 
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I found the final velocity, but when i tried to use the formula for distance, I found that I didn't have r sub p or T max and have no clue how to find them.
 
You need to post all the equations you are referring to and define any symbols in them which might not be completely obvious to readers. (Even the "relevant equation" you posted is not an equation.)
 
Psyguy22 said:

Homework Statement


A rocket in outer space has a payload of 4050.0 kg and 1.753·105 kg of fuel. The rocket can expel propellant at a speed of 4.300 km/s. Assume that the rocket starts from rest, accelerates to its final velocity, and then begins its trip. How long will it take the rocket to travel a distance of 3.82 ·105 km
Psyguy22, please look at what you posted. You did not mean 1.753·105 kg of fuel, you meant 1.753·105 kg of fuel. There's a huge difference between 184.065 kilograms and 17,530 kilograms.
 
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