How is Work Calculated for a Constantly Accelerating Rocket?

In summary, the conversation discusses the calculation of work done by a rocket traveling at a constant acceleration, taking into account the rocket's frame of reference. The suggested method involves integrating the velocity function of the rocket and multiplying by two to account for symmetry. There is also a mention of a time equation and a link that may be helpful in this calculation.
  • #1
Nabeshin
Science Advisor
2,207
16
If I have a rocket constantly accelerating at some rate a, (requiring some constant force F), I want to know how much work is done by the rocket to travel a given proper length.

For example, a rocket traveling to alpha centauri at 1g acceleration half way and 1g acceleration the other half. It would seem work would just be F*d, however, the d should be as measured in the rocket's frame of reference. Would a correct method of deriving the d to be to take the velocity function of the rocket, integrate from 0 to some t (half way point), and then multiply by two (symmetry) to obtain total distance traveled in the frame of the rocket?

General note: the function I'm using for the time between two points also requires the measurement d. The equation is:
[tex]t=\frac{c}{a_0} Cosh^{-1}\left[1 + \frac{a_0 d}{c^2}\right][/tex]

with t being as measured on the ship. To get the time to the mid-way point (required for the above approach), is it valid to just set d/2? (and also multiply by two to get the entire shipboard time for the full voyage)
 
Physics news on Phys.org
  • #2
This might be helpful.

http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.html
 
Last edited by a moderator:
  • #3
Thanks for the link, that's actually where I got the posted time equation.

The only possibly applicable equation is that under the section "below the rocket ..." but I don't think that's quite it. That equation gives the remaining distance, or current distance at any time T, whereas I want the total distance traversed in the frame of the rocket... Unless I'm missing some basic calculus I can't get what I need from that equation.
 

FAQ: How is Work Calculated for a Constantly Accelerating Rocket?

What is constant acceleration in a rocket?

Constant acceleration in a rocket refers to the rate at which the rocket's velocity changes over time. This acceleration remains constant as long as the rocket's engines are firing, leading to a steady increase in speed.

How does constant acceleration impact a rocket's journey?

Constant acceleration is crucial for a rocket's journey as it allows the rocket to overcome the force of gravity and achieve escape velocity. This acceleration also ensures that the rocket's journey is efficient and reaches the desired destination in a timely manner.

What factors affect the constant acceleration of a rocket?

The constant acceleration of a rocket is affected by various factors, such as the strength and efficiency of the rocket's engines, the mass of the rocket, and the resistance of the surrounding environment. External forces, such as air resistance and gravitational pull from other celestial bodies, can also impact the rocket's acceleration.

How is constant acceleration calculated in a rocket's trajectory?

The constant acceleration of a rocket can be calculated using the rocket equation, which takes into account the mass of the rocket, the exhaust velocity of the engines, and the amount of fuel burned. This equation is used to determine the rocket's velocity at any given point during its journey.

Can a rocket maintain constant acceleration throughout its entire journey?

No, a rocket cannot maintain constant acceleration throughout its entire journey. Once the rocket reaches its desired velocity, the engines will need to be shut off, causing the acceleration to stop. Additionally, external factors such as air resistance and gravitational pull will also affect the rocket's acceleration. However, the rocket's trajectory and velocity can still be carefully calculated and adjusted to maintain a relatively constant acceleration throughout its journey.

Similar threads

Back
Top